my 10 gallon trop tank is having a problem. ammonia is almost nonexistent but the nitrites and nitrates are off the charts! i just did an 80percent water change and there is no real apparent change in the levels.
5 danios 1 black skirt tetra
before water change
ph 7.9
ammonia less than .25
nitrite reading 5.0 ( i believe higher still reading 5.0 after water change)
nitrate reading 80 ppm after water change 40
don't yell at me but i'm running a hydrosponge 1 i asked about it and people told me i could try it out for so few fish, i'm going to get an over the top filter tomorrow.

How did the levels get sooo high? i used some of the old water from my 14 gallon to try and jmp start the cycling of the new tank. all the water parems were good when i used it. i am going to do another water change tomorrow, but how do i lower these crzy toxic levels????

please help don't want my fishies to die. they haven't shown any signs of stress. no bottom sitting, still swimming around like nothing is wrong. no gasping. no clamped fins. what is the deal? i know it isn't the kit i used because i used it on the other tank just before this one.

When was your last water change before the most recent 80% one?

How long has this new tank been set up?

how old are the test kits? sometimes they get old and can give crazy readings.

I love my sponge filters, but an uncycled sponge filter is still uncycled! Hope it gets turned around.

No reason to not do 100% water change matching temperature.

the last water change was a week ago. that is when i got it set up with the fish in it. it was 75% new water, and 25% cycled water from the old tank. the tank had originally been started a week before that because i thought i was going to have danio fry. at that point all it had was an air stone and a little bit of water in it. about 2 gallons i think.

i bought the master kit about a month and a half ago. i know it isn't the kit. it has been very good so far, i even cross checked it with a friend's kit. the 14 tanks readings were the same when i tested it. there is no doubt about it. the 14 is cycled and good, and the 10 has off the charts toxic levels of bacteria. i am doing another water change tomorrow.

should i go ahead and dump all the water, clean the gravel and plants, and start over from scratch???

like i said i'm getting an over the top filter and putting the sponge filter ( after i clean it ) into the 14 with the 2 goldies. added filtration can't hurt there. i just don't understand how my levels are so toxic after such a short time and that the fish don't appear to be having any problems.

so any ideas???

have you ever tested your water source?

One misconception you're under is that you said 'cycled water from the old tank'. Very little to none of the 'cycle bacteria' actually live in the water, so bringing over the water from the old tank doesn't really help. The good bacteria live in the gravel and the filter and the filter media, maybe a tiny bit on the walls, but not really any in the water itself.

The levels got high because you have an uncycled tank that you didn't touch for a week.

Use your test kits to measure your tap water. If it measures very high there too then there's a chance that it is the test kit that is off.

I can't speak too much about tropical fish, but do another water change, and again, etc until the levels come down to a better level, and keep a closer eye out from now on.

the tap is negative for both bacteria
the ph is 7.4
no ammonia

the test kit isn't off, it reads everything else normally. it is just that tank. the lfs guy told me to use water from the other tank when doing the water change today, and not the tap. he said the fish may not be reacting to the high levels because they became used to them when they were slowly climbing. i don't know. i am going to put the 5 to 15 filter from the 14 gallon on the 10. i know that will help kick off the cycle because that filter is in the cycled tank.

i bought a 10 to 20 filter for the 14 gallon because i have 2 goldies in there. i figured even though the space is smallish 12x filtration can only help there. my question is this. after putting in the new filter, will that tank have to cycle all over again, or will there be enough in the substrate to maintain it as a fully cycled tank?

just rechecked the levels in the 10 gallon. nitrites are down to 1 ppm and nitrates are down to 10
MUCH BETTER than last night.
i'm switching out the filters anyway, definitely can't hurt. the goldies need more filtration.

anytime you start off a new filter or clean one squeaky clean you will have to cycle the filter over again.

okay, that might be why my readings are getting a little weird in the 14 now.
ammonia 0
nitrite 0
nitrate 10 ppm

i've had the new filter running for about 24 hours now, and the goldfish aren't bottom sitting but are swimming and staying near the bottom. the larger one keeps hiding by a big plant and the smallish one is staying near the back by some smaller plants. could it be all the extra water flow or the change in the cycle? there is now a hydrosponge 1 and a aquatech 20 to 40 gallon filter in there. is that overkill????

have i just royally screwed up or is it something they are just adjusting to?

anyone know anything about that??

Sorry angelnikki, I'm having trouble following your situation. Could you please describe in more detail what tanks you have, which is new, how many fish are in each, etc.

How have they been since then? How have the water readings been?

To respond to a couple things you said:


I don't think I've ever heard of a test for the bacteria. What tests are you talking about here?


I'm very skeptical that this is the case. If you get used to living in a smoke filled house it doesnt make a breath of fresh air a bad thing. Keep using dechlorinated tap water for your changes to keep the levels down as much as necessary.