What is going on in my tank? Fish are dying?

Question

My tank ran empty for 3 weeks and then added pleco and corys. Waited 2 weeks and add a group of 7 juvenile african ciclids. My exterior filter is rated for twice the size of my aquarium (40 g), I have been checking the water quality (ph, no2, no3, hardness, and temp) everyday and have not had any spikes. Already did one water change also. So far I have lost 1 cory ( after bringing home it looked a little beat up), I cant find the pleco anywhere, and now one of the ciclids is starting to "swim irratic" but is going nowhere and is hiding in the amazon swords (fake). This one looks to be on the way out also and I cant figure out the problem. The cory looked lethargic and died the next day. No sign of ick either. Any ideas?

Now a second cory is looking lethargic also.

Answer 1

You left out ammonia. I assume you are testing for it too? Your tank is prime for an ammonia spike. You have added alot of fish very quickly. Running your tank empty only wasted electricity unless you did a fishless cycle. There is a very strong possiblility that the cories are getting beat up by the cichlids, even if they are juvies. Plecos do not disappear. My dog has eaten jumpers, I know because I caught her. Check behind the aquarium too. If you don't have a dog or cat and it isn't behind the aquarium, then it is still in there somewhere. You should look for it very well, and move around the decorations if you have to. A dead pleco in a newly cycling tank can be disasterous.

Answer 2

I'm an avid aquarist and had this problem over and over again in the beginning. The thing is is that most fish that come from anywhere that isnt a petshop tend to be sick to begin with. I found that good petshops offered the highest quality fish. Also, the whole experience of being transported is very stressful for fish and its common for a few to die off. One thing I did for my new fish was add a few squirts of of Stress Zyme.... it added a protective slime coat on their bodies and greatly helped them cope with the stress. As well, when I first set up my ten gallon I had no luck with keeping fish alive ....so with some advice I was told to culture it first with a goldfish. You add the goldfish (because they seem to be the most hardy) 1 or 2 ...go for the common.... and let them live in the aquarium for about 2 weeks ....dont ever do a total water change even after you've added your final fish.... only do a partial like 20%. The goldfish's waste and the food you feed it with that he doesnt eat all decompose like peat moss and it creates a culture of tiny organisms which are vital to a fish's health and natural environment. When you are ready to add your final fish, remove the goldfish and only buy a few ornamentals ....see how they react ....if they seem to be fine and eating well and not darting off into the darkness after about 3 weeks then it should be safe to add new fish ...a few at a time. And as I'm sure you know ...make sure your heater is working and when buying new fish watch them in the petshop aquarium for awhile and observe their behaviour. I usually sit there for ten minutes. If they act curious, playful, and pick at their surroundings then they should be healthy ....as always never get a fish that has torn fins, missing scales, white fuz, bloated belly, missing eye etc.....even if you really like it!!! LOL gosh....I rambled alot

Answer 3

Like said above where did you get your fish? Maybe thereare too many fish for your tanks ecosystem, and it is overcrowed. You have not mentioned you ammonia levels so ammonia poisioning could be to blame.Other than that everything seems to be perfect Try putting in live plants and never purchase from a tank with a dead fish in it. Though I am not so sure if using a bigger filter really is better. Also interal parasites spreading from fish to fish may be to blame. Good luck figureing out what is wrong!

Answer 4

How old is your test kit? I would recommend getting your water tested at a pet store for a confirmation of your readings.

With no fish in the tank for three weeks, it's very possible that your bacteria which convert the ammonia to nitrite and nitrate have died for lack of a "food" source, since they rely on the ammonia your fish produce. Your tank may be cycling again.

Answer 5

letting your tank sit idle for 3 weeks did it no good and may have done harm. take a sample of your water to a reputable fish store and ask them to test it for you, i would guess that you are having fluctuations and your fish are reacting to them (even tho your testing indicates otherwise).
if you tear down and start over, instead of letting the tank sit, put in 2-4 zebra danio. they are inexpensive, help condition the water and are very hardy. if you have a good pet store around, i would tell them what you are doing, and see if they will sell you the danio then give you credit towards the fish you really want to keep if you bring the danio back.

Answer 6

You have done one waer change in 5 week's? Thats your problem, and you added to many fish into the tank, Do another water chnge,

Good luck

~ GG

Answer 7

do u have a filter if dont get one