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Hi there, i liked your forum so i joined it wishing your help. don't be shy and help me out, OK ?

now for real i have this small tank and i started with convict cichlid, they produced twice, so i though before they take over the Tank i thought i should put some other cichlids with them.
i have about 9 fishes from the 1st gen. (about 3months old) and i had 9 others from the 2nd gen. (about 1month)
after i added the new fishes i have only 2 fishes from the 2nd gen. and that's it.

i use this food + brine shrimp + blood worms.


but what i need is your tips and advises on:

how often i have to clean the water? (about 1/4 of the tank)
how often i have to clean the filter?
do i have to put these chemicals on every time i change the water? (the ones in the pic above)

what is have now is 2 adults + 9 from the 1st gen.+ 2 from the 2nd gen. Convicts.

1pleco

2 clown lochs


2 green texas
4 green texas

so in total thats 10 adult fishes + pleco + 9 3mon. fishes + 2 1mon.

wait there was something weird right ? why 2 and 4 GT ? why not 6 ??
well actually i entered two shops seeking green texas, each shop had different fish and he would call it green texas
so i dont know what i have now
so anyone please who know anything please share your info with me
thats 1 type
thats the 2nd

of course a normal question to be asked is how to define male/female from those fishes ?
and why some on them have a really gray color on them almost black, while when i purchase them from the shop they were so bright ?
although even now they look health eat well swim good ..etc
thanks in advance for your help, n sorry for asking a lot of questions

Welcome to the forum.

I would say the best way to get all your questions answered is to first answer a few of ours.

Tank size? 30 gallon
Filtration?
Full stock list with sizes?
Current maintenance schedule?
Water parameters. Ammonia? Nitrite? Nitrate?
Introduce yourself. Tell us about you.

this should give everyone a good idea of where you are and the direction you may need to go.

hi, n thanks for the Super Fast reply..

well,,
all my fish is :
1pleco
2clown loach
2 green texas
4 unknown cichlids
13 convicts (2 adult, 9 of 3month old, 2 on 1month)
i don't have a clue about how to guess there sizes

i have Tetera tec filter ex700
eheim air pump 100
eheim jager 3605 heater

i know nothing about the water parameters sorry, so please teach me about it.

but i usually change about 1/4 of tank water every week. if not, i sure don't ignore it seeing too much dirt inside
about filter i clean it with tank water each 2 months, sometimes even less.

i'm from Kuwait, this is my first tank, i took interest in home aquarium tanks after seeing one guy i met in training course, he has 2 freshwater tanks
1 : only Convict cichlid.
2 : all sort of cichlid gang mixed but medium size, he says although they are African Malawian cichlids..etc what ever fish he add to them they will become one hand and will strike the new fish
3 : marine tank, he bother his self and catch a fish from the sea, use a battery air pump.. put them in his tank and life is good thats it.
so from his talking and so.. i decided i want to put one.

by the way i just checked the convict led new eggs in there hideout

they will takeover my tank for sure

Please include sizes for your fish.
To learn about water parameters, here's a link to an informative article:
http://www.oscarfish.com/article-home/water/76-what-is-the-nitrogen-cycle-and-how-do-i-do-it-to-my-tank.html

I also recommend you take some time and browse most of these articles:
http://www.oscarfish.com/article-home.html

Breeding convicts can mean trouble for the other fish, but that's probably the least of your worries.

but that's probably the least of your worries.

OMG !! please dont scare me..

i want to be good with those cichlids ..

anyhow thanks for those article i would definitely pass by them.
and please come back for more info.

The first article that Tom posted is essential for any aquarium. It's worth more than a passing glimpse. The more you understand them, the better off you will be in this hobby.

Okay. Welcome to the forums! This thread is sort of a mess. Let’s try to organize some of this so we can all get a good idea of what is going on here and try to get you some help with your situation and answering your questions.

Here’s what I recap from all this information as far as your setup…

Cichlids wrote:-30 gallon aquarium
-Tetratec EX700 Canister Filter
-Eheim Air Pump 100
Eheim Jager Model 3605
No known water perimeters

Filtration & Heating
Typically with filtration a good cardinal rule is if you are using hang on back power filters to have 10x turnover of the tank volume. Canister filters are more efficient at what they do so 4x turnover the tank's volume is recommended for canisters. So having a 30g tank you want either 300gph for a hob power filter, or 120gph with a canister. Keep in mind the cardinal rule assumes your tank is moderately stocked. Your Tetratec EX700 Canister is 700LPG which equals 184GPH. With how overstocked your tank is I would definitely recommend more filtration. Now that's only if you decide to keep it overstocked. Long term I would recommend deciding what you really want to do with the tank, rehoming most of the fish, and having the tank properly stocked. That way you would be decently filtrated, and stocked.

Your Eheim Air Pump pushes 26GPH and I'm assuming you are using the basic air diffuser that comes with this model? If so it's really not adding to filtration but does help add oxygen to the water with the bubble agitation that takes place at the surface of the water. It's a nice bonus since you are very overstocked and under filtrated for what you have atm.

As far as the heater goes, the 3605 model is 125W. That should be fine for a 30g. If it keeps your tank between 78-82 then it's good to go. I never really payed much attention to specific heater brands myself. As long as it keeps the water at the temp it needs to be I considered it good to go.

Your water perimeters are unknown. I'm assuming this means you don't have a test kit to check these readings. A test kit is 100% mandatory for any fish keeper. It's vital to maintaining a healthy tank by being able to check your water's ammonia, nitrite, and nitrate levels on a regular basis so you have an idea of your waters perimeters and how often you need to perform water changes to keep the water at an acceptable level to maintain your stock's health. Typically when your nitrates get to 20ppm it's time to do a water change. You need to get a test kit asap. Don't waste your money on the dip strips as they are very unreliable and inaccurate. Make sure to obtain a chemical test kit. Most everyone here recommended API Freshwater Test Kit. http://www.bigalspets.com/API-Freshwater-Master-Test-Kit/dp/B000255NCI?ie=UTF8&id=API%20Freshwater%20Master%20Test%20Kit&field_product_site_launch_date_utc=-1y&field_availability=-1&field_browse=3007699011&searchSize=12&searchNodeID=3007699011&searchPage=1&searchKeywords=api%20freshwater&field_keywords=api%20freshwater&class=quickView&refinementHistory=brandtextbin%2Csubjectbin%2Ccolor_map%2Cprice%2Csize_name&searchRank=salesrank

Let's talk stock now. From what I've compiled this is the stock in your current tank.

Cichlids wrote:2 adult breeding Convicts
11 juvenile Convicts
1 what appears to be common or sailfin pleco
2 clown loaches
6 supposed green texas cichlids (not 100% ided)

First things first. If you keep those two Cons together they will continue to breed. If you don't have a continuous source to rehouse the Cons (like using them as feeders for another fish or a local fish store that will agree to take them) then I recommend you rehouse one. Not only will they continue to over populate your tank, but they are very nasty fish when breeding and will likely harrass or harm any other stock with them. Specially in a tank so small.

The common or sailfin pleco is simply much too large a fish to be kept in a 30g tank. Plain and simple. Minimum tank size for a SINGLE Sailfin would be IMO a 55g and that is with NOTHING else stocked with it and the water changes would still have to be weekly/bi-weekly and large. He needs to go.

The Clown Loach are fine and fun to watch but they are schooling fish that are more secure/comfortable/active when in a decent sized school of their own. Two isn't a very suitable number for a group of schooling Clown Loach. If you do want to keep them I'd at least bump them up to 6 or greater. Also keep in mind although CL do grow extremely slow, they can reach sizes up to 12" AND get some serious girth/size to them. They won't be able to be housed in a 30g tank for life. That being said they are also pricey fish in the hobby at the moment so it might be more beneficial to you to rehouse them and find a more appropriate schooling bottom dweller like a corydoras cat, instead of spending the money on more CL without a proper sized tank for them in the far future.

Texas Cichlids can be pretty aggressive and do get fairly large. No way I would have more than 2 in a single 30g, and realistically I wouldn't even have one. They are a medium to large cichlid and IMO would require at least 50 gallons for a single Texas. Now 6, that's quite bananas. Definitely a blood bath waiting to happen. As far as if they truly are Texas Cichlids we need to figure that out too! I'm no expert on Texas but to me they definitely BOTH appear to have some Texas in them but also both look like a hybrid. Texas are a quite commonly hybridized cichlid. A. looks like a TexasXbp IMO. B. I'm not really sure. I can confirm that IMO there is definitely some Texas in there but not sure if he's mixed with something else, or maybe even a true Texas. We'll have to wait on a few others opinions on this subject. What does everyone else things?



Okay, Your questions.

Cichlids wrote:how often i have to clean the water?

Depends. Generally a 50-70% wc a week is common. Here's really how people measure their water change frequency. Test your water with a quality chemical test kit. If the tank is fully cycled and has an established bb colony in the filter media then you should always read 0 ammonia, 0 nitrites, and some sort of nitrates. When the nitrates hit 20ppm then it's time to do at least a 50% wc to lower the nitrates to a healthy level for the fish. In a nut shell you do as many wc as you need to maintain your nitrate levels in your water below 20ppm. With a tank size and stock list we can typically give you an educated guess on how often you will need to do a wc and how much.

Cichlids wrote:how often i have to clean the filter?

Typically people maintenance canister filters once a month. Some wait longer, some more frequently. I generally would do this once a month by rinsing down all the media in the canister with tank water (NOT TAP WATER), and reassembling. There are little catches, like if you are stocking a fish that is known for a heavier bioload, or overstocked, you might want to consider doing maintenance on your canister more frequently. Tank of guppies or tetras? You can probably get away with doing them less than once a month.

Cichlids wrote:do i have to put these chemicals on every time i change the water?

Not all of them no. The only chemical you need to use on a regular basis in one that remove harmful elements from the tap water that you use to do water changes. Ammonia, chlorine, chloramine, heavy metals, etc. We refer to these as water conditions. If you don't use a water conditioner when doing a water and put non conditioned tap water into your tank, it will run through your filter media and the chlorine and chloramine will completely destroy the beneficial bacteria in your filters and cause your tank to cycle all over again which is very harmful for your fish. (ammonia and nitrite spikes) I'm not going to go over that in detail since you need to read through the nitrogen cycle article. Your Aquasafe water condition seems to treat tap water for chlorine, chloramine, and heavy metals so that will do for now, but I would recommend a product like seachem prime. Most of us here use Prime. It's the best bang for your buck, the amount you have to add per 50g is minimum so it last a long time, and it treats chloramine, chlorine, binds heavy metals, and converts ammonia to ammonium which is just less harmful in your aquarium. (no one nit pick this!, lol)

I hope this information helps and also organizes this thread of information a little so everyone else can better provide their advice and input. On a final note you need to read through the entire New Oscar Owner Information Packet http://www.oscarfish.com/article-home/oscars/52-new-oscar-owner-info.html INCLUDING the hyperlinks. I know you don't have an Oscar but you are housing medium and large very similar cichlids and all the information in that package can be used in your situation except the few minor tid bits that pertain specifically to Oscar.

I also recommend you read through this entire article. http://www.oscarfish.com/article-home/water/76-what-is-the-nitrogen-cycle-and-how-do-i-do-it-to-my-tank.html This really is mandatory information for a fish keeper to know. The article isn't painfully long, and contains very crucial knowledge for a fish keeper.

Hope to hear back from you soon and surely we can help you get your tank on track where it needs to be.

Tom wrote:Please include sizes for your fish.
To learn about water parameters, here's a link to an informative article:
http://www.oscarfish.com/article-home/water/76-what-is-the-nitrogen-cycle-and-how-do-i-do-it-to-my-tank.html

i did read this article and i now understand what is a Nitrogen cycle,and i understand some of what happens in my tank
and i by the way those two bottle from the first post i use for the tank "one is anti-chlorine the other one is useful bacteria" told my friend
thanks for sharing

about getting there sizes how do i do that ?

Cichlids wrote:

Tom wrote:Please include sizes for your fish.
To learn about water parameters, here's a link to an informative article:
http://www.oscarfish.com/article-home/water/76-what-is-the-nitrogen-cycle-and-how-do-i-do-it-to-my-tank.html

i did read this article and i now understand what is a Nitrogen cycle,and i understand some of what happens in my tank
and i by the way those two bottle from the first post i use for the tank "one is anti-chlorine the other one is useful bacteria" told my friend
thanks for sharing

about getting there sizes how do i do that ?

You read my response? Yes, we know what the chemicals are... As I already mentioned the Aquasafe is a water conditioner for tap water. It needs to be used every time you do a wc to condition the new tap water you add to your tank. There are better products out there but it will suffice for now.

The API Stress Zyme claims to have beneficial bacteria in a bottle.

Improves the development of the biological filter and helps clean a dirty aquarium. Contains over 300 million live bacteria per teaspoonful. Breaks down organic compounds that cause dangerous conditions such as ammonia and nitrite poisoning and low oxygen levels. Continuous use assures an active biological filter, cleaner aquarium, healthier fish and good water quality. No refrigeration necessary. Use when setting up and maintaining an aquarium. For use in fresh and saltwater.

Couple of things. First, you don't need any chemical to improve your biological filtration. If your tank is properly cycled then you should have all the beneficial bacteria colonies established in your filter media. Second, no chemical is needed to help "clean a dirty aquarium." If you have your tank properly cycled and maintain and regular wc schedule and maintenance for your filters then your tank will stay "clean." Finally, from a chemistry view point, IMO (and many others) it's not even possible to bottle up the beneficial bacteria that is produced at the end of the nitrogen cycle and store it in a bottle, and even if it was I believe the bb would need to be kept at a certain low temp to stay alive. In short, there are many products that "claim" to bottle bb and say you can dump it in your tank and instantly cycle it but really it's just a gimmick. To properly cycle the tank you need to introduce a source of ammonia via livestock of some sort, or chemically such as per ammonia, or another source of ammonia like raw shrimp, and then wait the proper time (usually 3-6 weeks) for the nitrogen cycle to take place and develop. You don't need to be using this chemical in your tank, the only chemical you need to consistently use on a healthy fw aquarium is water condition for your tap water, and adding unneeded chemicals to your tank is just asking for problems.

As far as telling the size of your fish, this is pretty simple.... You look at them and guesstimate?... To help you do so you could even put a tape measure running from the left to right of your aquarium and eye ball their size when they swim by it... There is no "special technique" for getting your fish's sizes. You just eye ball it bro. Besides that they can always be removed from the tank and layed down on a soft towel and measured with a tape measure but I really don't recommend doing that for no reason and stressing the fish out. The majority of us get a quick out of tank measurement when already having to take the fish out of the tank, like when they are being moved from one tank to another.

Jon M wrote:You read my response? Yes, we know what the chemicals are... As I already mentioned the Aquasafe is a water

The API Stress Zyme claims to have beneficial bacteria in a bottle.

Improves the development of the biological filter and helps clean a dirty aquarium. Contains over 300 million live bacteria per teaspoonful. Breaks down organic compounds that cause dangerous conditions such as ammonia and nitrite poisoning and low oxygen levels. Continuous use assures an active biological filter, cleaner aquarium, healthier fish and good water quality. No refrigeration necessary. Use when setting up and maintaining an aquarium. For use in fresh and saltwater.

As far as telling the size of your fish, this is pretty simple.... You look at them and guesstimate?....

yeah of course i saw ur reply.. but since you shared too much info with me, i didnt like to leave with just a fast reply.
but as for this post from you first of all thanks for explaining it more and now i know:
1 : tank need to be conditioned.
2 : bb can't be bottled.
3 : a good conditioned tank doesn't necessary need bb to be added.
right ?

ok what about this bb ?

about there size i would never take them out to measure them noway i too afraid to do so.
and even when i think about it the fish will just keep fliping and moving till there is no breath man !!
i will try to guesstimate only
last thing but not least THANKS for calling me bro

my fish sizes is
1 male convict cichlid 2"
1 female con. unknown she is always busy or hiding taking care of the eggs. but its less than 2" and sure more than 1.5"
2 1month convict are .5"
9 convict from the 1st. Gen. although they were born in same date they aren't the same size (why?)
smallest one is 1" largest one is 1.5" (still not showing male/female difference)
pleco is 4" i guess (the reason i took this type even though he can get so big is simple, he is the only one available in my home)
if he get over size i can send him back to the fish store.
4 green texas are about 1.5''
2 green texas are about 2.5''
2 clown loach are about 1.5''
i know my tank is small didn't know it was small until i saw some tanks in youtube i was so amazed
but i did some reading i browsed the net searching for e-books about cichlids, and found this book by:
Dennis L. Bangerter
so i tried to collect fish from the same family, and that was the best fishes i saw, i saw once gold severum it fits 30g tank very well. but now its out of stock.
and by this forum i saw in convicts faqs, that there tank mates are green terror, green texas, blood parrot,..
i was planning on taking some or maybe all of the 9 convicts once they're adult bcz i know my tank is small.
finally i was able to know my fish size thanks to you Jon M, but i think you own me aspirin tablet now coz my eyes are like
the fish were afraid from the measuring tape i was try to keep them in my site ..
thanks bro.

Jon M wrote:Okay. Welcome to the forums! This thread is sort of a mess. Let’s try to organize some of this so we can all get a good idea of what is going on here and try to get you some help with your situation and answering your questions.

Here’s what I recap from all this information as far as your setup…

Cichlids wrote:-30 gallon aquarium
-Tetratec EX700 Canister Filter
-Eheim Air Pump 100
Eheim Jager Model 3605
No known water perimeters

Filtration & Heating
Typically with filtration a good cardinal rule is if you are using hang on back power filters to have 10x turnover of the tank volume. Canister filters are more efficient at what they do so 4x turnover the tank's volume is recommended for canisters. So having a 30g tank you want either 300gph for a hob power filter, or 120gph with a canister. Keep in mind the cardinal rule assumes your tank is moderately stocked. Your Tetratec EX700 Canister is 700LPG which equals 184GPH. With how overstocked your tank is I would definitely recommend more filtration. Now that's only if you decide to keep it overstocked. Long term I would recommend deciding what you really want to do with the tank, rehoming most of the fish, and having the tank properly stocked. That way you would be decently filtrated, and stocked.

now really thanks for this big reply, i was reading this for more than one time
Ok, so about filtration you're saying that my tank is overstocked and this filter isn't enough in case i want to keep the tank overstocked.
well, i was guess its overstock, i know my tank is small, but i dont know my filter or my tank limit. and i dont plan to keep all the 11 convict, at most i thought i would keep a pair. and thats all.

Your Eheim Air Pump pushes 26GPH and I'm assuming you are using the basic air diffuser that comes with this model? If so it's really not adding to filtration but does help add oxygen to the water with the bubble agitation that takes place at the surface of the water. It's a nice bonus since you are very overstocked and under filtrated for what you have atm.

does that means that i can keep the tank overstock because of the air pump ?
yeah its the basic one with the basic diffuser.

As long as it keeps the water at the temp it needs to be I considered it good to go.

my heater is ok.

You need to get a test kit asap. Don't waste your money on the dip strips as they are very unreliable and inaccurate. Make sure to obtain a chemical test kit. Most everyone here recommended API Freshwater Test Kit.

i will get a test kit, and thanks for telling "dip strips = waste of money" but i'm guessing that the market here have tetra's only, anyhow i hope i can find many brad so i can chose.
but if the water parameter is only telling me "now you need to change 1/4 water" wont it be enough to just change every week ?.
and after i get the test kit how often i should make the test ?

I have a 150 gallon tank that is almost at its stocking limit and will be as some of the catfish grow. I change 90% of the water weekly. This has been adequate so far to keep the nitrate levels low enough. Once it gets to the point where 90% weekly is not enough, I will change the stocking list.

Right now it is mostly fish from Malawi, some 6 years old. I am introducing Florida native fish and it will eventually be entirely Florida native. At that point, it will be understocked again. I expect the need to change over will be within 6 months.

You will be fighting this battle as long as you have a pair of convicts. Maybe part of the answer is to pick the male or female and rehome the other. If you wish to raise convicts, I would get another tank to deal with the fry. And find many people or shops that want hundreds of convicts.

You will want to test often. And you want to change enough water of often enough to keep the nitrate level below 20.

If you keep those two Cons together they will continue to breed. If you don't have a continuous source to rehouse the Cons (like using them as feeders for another fish or a local fish store that will agree to take them) then I recommend you rehouse one. Not only will they continue to over populate your tank, but they are very nasty fish when breeding and will likely harrass or harm any other stock with them. Specially in a tank so small.

that is one new info to know now, Convicts will continue to breed but i cant take them off, i like the male, and the female is colored very beautiful.
i know the tank is small, and from the 11th babes i'm planning to remove them from the tank, or maybe i'll will only keep just one pair total will be 4Cons.

The common or sailfin pleco is simply much too large a fish to be kept in a 30g tank. Plain and simple. Minimum tank size for a SINGLE Sailfin would be IMO a 55g and that is with NOTHING else stocked with it and the water changes would still have to be weekly/bi-weekly and large. He needs to go

believe or not, but he is the only one available in my home. but i need him since he is a cleaner fish as i was told. and i see that the tank is getting small for him, i'll just exchange him for smaller one, but he is needed in every tank right??

The Clown Loach are fine and fun to watch but they are schooling fish that are more secure/comfortable/active when in a decent sized school of their own. Two isn't a very suitable number for a group of schooling Clown Loach. If you do want to keep them I'd at least bump them up to 6 or greater. Also keep in mind although CL do grow extremely slow, they can reach sizes up to 12" AND get some serious girth/size to them. They won't be able to be housed in a 30g tank for life. That being said they are also pricey fish in the hobby at the moment so it might be more beneficial to you to rehouse them and find a more appropriate schooling bottom dweller like a corydoras cat, instead of spending the money on more CL without a proper sized tank for them in the far future.

its because i thought of my tank is small that i couldnt take more, and he guy from the shop he told me its a bottom tank cleaner fish. he told 2 is enough.
also when they gets big, i can exchange them right, and thanks for telling they grow slowly, so i can keep them for a while.

Texas Cichlids can be pretty aggressive and do get fairly large. No way I would have more than 2 in a single 30g, and realistically I wouldn't even have one. They are a medium to large cichlid and IMO would require at least 50 gallons for a single Texas. Now 6, that's quite bananas. Definitely a blood bath waiting to happen. As far as if they truly are Texas Cichlids we need to figure that out too! I'm no expert on Texas but to me they definitely BOTH appear to have some Texas in them but also both look like a hybrid. Texas are a quite commonly hybridized cichlid. A. looks like a TexasXbp IMO. B. I'm not really sure. I can confirm that IMO there is definitely some Texas in there but not sure if he's mixed with something else, or maybe even a true Texas. We'll have to wait on a few others opinions on this subject

as i was reading in some cichlids e-book by:Dennis L. Bangerter, it was as you said texas minimum tank size is 50g, i was looking for gold severum, but i didnt buy them fisrt time in site and now they are finish from the market , so as Cons are aggressive fishes and being in same family group and me being un able to resist there beauty i took them in. the one from the pic. A i saw in shop in bigger size, looked just like gold severum, all round shape
the other one look like a real green texas, but both shop said its green texas.
i really want to know about there color sometimes they turn gray, or partly gray.. why ?
and how do i define m/f of them ?
also my fishes size being known now what is my tank limit ?

Always stock your tank by the adult size of the fish. Not the juvenile size that the shop has.

Of the fish you have now, honestly. Your tank's limit is probably just the convict pair.

Don't get a severum to add to what you have. I might recommend one to a 30 gallon if it was the only fish in there.

For a 30gallon tank, you shouldnt be looking at medium to large cichlids.

There are lot and lots of cichlids that would do well in that tank. For example, dwarf cichlids or African shell dwellers. Maybe a small colony of Brichardi or even Yellow labs. Or, as I said, the convict pair.

Ted is bang on the money of course.
The guys at the fish store want to sell you stuff, we don't.
We just want you to have healthy fish and try to explain why.

Ted wrote:Always stock your tank by the adult size of the fish. Not the juvenile size that the shop has.

Of the fish you have now, honestly. Your tank's limit is probably just the convict pair.

Don't get a severum to add to what you have. I might recommend one to a 30 gallon if it was the only fish in there.

For a 30gallon tank, you shouldnt be looking at medium to large cichlids.

There are lot and lots of cichlids that would do well in that tank. For example, dwarf cichlids or African shell dwellers. Maybe a small colony of Brichardi or even Yellow labs. Or, as I said, the convict pair.

adult size fish is not always available, another thing, for the texas in pic A the adult size is 3 times the one i got price :O.
you mean for my tank, the limit is only one pair of convicts ??!!
i tried to mix american african cichlids before they were all almost the same size too, i ended up removing dead fish every day and some times eaten dead fish while in other times they just end up missing !!
i took yellow lab, Demasoni, Frontosa, Buttikoferi, Green Terror (only few days. coz i sent them back to the shop ), Kenyi too.
Note that all those mentioned ended up dead, but not all of them met green terror, so even now i dont know who did it.
so i thought i should just stick up with the same family, so i chose american cichlid.
i know the texas could reach 1' of maximum recorded size, but i can always send bigger fishes back to the shop, they will take them for more $$
but i'm really stuck with the tank i really know how small it is. i didnt know much about it from before. what to do.

No, I didn't mean buy adult fish, I mean stock as if they are adult sized. Then you will never have problems,

If the adult size of a Texas cichlid is 1foot, then it's too big.

You tried African cichlids, you also listed some of the most aggressive species. A 30g is not suitable for those. If you stuck to JUST yellow labs, then you might get away with it.

You ask what to do... Since you have a 30galllon tank an you are stuck with it.

So you need to select suitable fish. So far not many of your selections have been.

Here is what I would do:

1. Return everything to the shop.
2. Stop reading books about fish,especially one with source material from a fish sales web site.
3. Select fish suitable for your tank. If you really want cichlids, go with the smaller species. Rams, Apistos, shell dwellers
4. Consider the adult size of every fish BEFORE you buy it.
5. Stick with Oscarfish.com. We've been around for more than 10 years and we have literally 100s of years of combined experience. Web forums are always going to be more accurate and up to date than any book.

No, I didn't mean buy adult fish, I mean stock as if they are adult sized. Then you will never have problems,

Thanks a lot, what was more clear advice, and more convincing.

yeah i know 1foot is too big, and as all other fish i plan to change them once i see the tank is getting smaller for them.
or if they manage to get my love by that time, i might try to force a bigger tank in the house
shop policy is they take only fishes that will benefit them, if they have the same fishes now they wont take it, but if my fish gets bigger, i hope that they will take them, or i will just have to sell them for lower price, i'm ok with that too , not for the texas i think they worth more, cons are cheap so its ok.
i know i'm talking about living beings so send them to the shop is better than sending them to a friend and make them a feeder fish.

Cons max. size is 6" : aggressive
severum max is 8": semi-aggressive ( which is why i didnt take them in)
can be kept in 30g tank, but i guess wont be ok together.

green terror 8" : aggressive
jack Dempsey 10" : aggressive
texas 1' : aggressive
minimum tank size 50g

may i put the e-book link? so that everyone can check it out

i entered the forum bcz i'm in need for practical experience.

the thing is i put those together because i like how they looked. thats it. when i feel they got bigger or the tank crowded i will remove some or force is bigger tank.

I think you have gotten lots of practical advice. What is frustrating is that it seems you don't want to receive it.

I looked at the ebook and the first few pages. It says it uses source info from Drs. Foster and Smith, specifically Liveaquaria.com. Retailers of fish always downplay the size of the tank needed to keep fish. If they were more accurate, they would be excluding themselves from more potential customers. They want the money, not the welfare or the fish. Here, we make no money from spending our time answering questions and giving advice. We do this because we like fish. And we like YOUR fish enough that we don't want them to suffer.

Edit: thanks for giving me the link to the whole ebook. You can post it here. I ask, how can one fish that grows to 1 foot require 50 gallons and another that grows to the same size with roughly the same shape need 70?

And how can you trust someone who says 30 gallons is the requirement for both a Severum and an Apisto? a full grown severum can eat an Apisto!

here is the book
http://freepdfbooks.tripod.com/downloads/cichlids.pdf

I think you have gotten lots of practical advice. What is frustrating is that it seems you don't want to receive it.

yeah i think i've gotten lots of practical advices, and i have received it, and ready for more, i really respect all your posts.
honestly i put the book to be under your practical test, i mean for people who have experience about the subject who can tell if what is written is true or not>

And how can you trust someone who says 30 gallons is the requirement for both a Severum and an Apisto? a full grown severum can eat an Apisto

i guess for a grown severum 8" to eat full grown apisto 3.5" thats normal.

anyhow i really appreciate the forum, thats why i came in the first place.
by the way i just got my test kit. (tetra of course) i really didnt find other brad all are finished from the market.
it has 2 pH bottle, NO2 bottle GH bottle (german hardness), KH bottle (also about hardness ).
the NO2 test is two parts, result is NO2 <0.3mg/l