I have 1 violet goby, 1 dojo loach, 8 guoramies, and 4 black fin sharks, and 6 zebera danios.
plus two angels and a bala shark?
Don't mean to sound overly critical, but just for future reference, that's
way too many fish for an uncycled tank - but it's a common mistake that many beginners make. Next time you'll know. The ones you lost were almost certainly due to ammonia or nitrite poisoning.
You're in the right place to get help, though. You'll be on the right track in no time.
Tstenbeck gave you the right advice. Right now you need to water change as necessary to dilute the toxins sufficiently to keep your fish alive. Your tank will cycle in time regardless, but if water changing slows the process down then it will just have to do so. IMHO, you could be looking at a total tank die-off before the cycle completes otherwise.
All but the most sensitive fish can actually tolerate nitrite in small quanitites fairly well for a time, but with the bioload you have your nitrite levels are going to get incredibly high (they're probably well beyond the 10 ppm where your test "tops out" already). As with most things, there are some differing opinions on how much nitrite your fish can tolerate semi-comfortably. If you were cycling under well-controlled conditions and with a small bioload, I would advise you to not even worry about it, but considering the number of fish you have we can't afford to do that. The nitrite spike will generally last two or three weeks, during which time it continues to build and build and build - and your fish may well be beyond help before the cycle completes.
My personal advice would be this:
To get the nitrite level down, do a partial water change (20% or so). After a few hours, retest for nitrite. If it's still too high, do another partial change. Wait a few hours. Retest. If necessary, partial water change. Repeat ad infinitum - testing and partial water changes spaced a few hours apart - until nitrite gets down in the 4 to 5 ppm range (many will advise you to get it down to one ppm, and you can if you choose to, but it will take a lot more work, will delay the cycle longer, and in my opinion is unnecessary - but if it makes you feel better to get it down that low, then by all means do so). It may take several water changes, but it will get there. Remember, your nitrite test tops out at 10 ppm, but the nitrite level is likely much higher. Until you get it below 10 ppm, your test will look like it's not coming down, but it is. Getting it there is the start, now you need to maintain it until the cycle completes.
Test daily for at least the next few days, and do whatever partial water change is necessary to keep nitrite in the "safe zone". If daily water changes are required (which seems pretty likely), two "half" water changes distributed through the day are better than one large one, if you are able and willing to do that - but one large one is a heck of a lot better than none. After a few days, you may be able to figure out the frequency and amount of water change necessary to keep it there, making daily water testing unnecessary (unless you want to). You will want to test every third day or so, though, so you can know when the cycle has completed, and you can stop fretting with these water changes and drop back to standard maintenance. It will have cycled successfully when three things happen.
1. Ammonia drops to zero, and stays there, AND
2. Nitrite drops to zero, and stays there, AND
3. Nitrate is present, and increases steadily.
Since you're currently in the nitrite spike phase, you can be pretty sure your cycle is finished when you get conditions 1 and 2 and they hold for a couple of days. My guess is you've still got a couple of weeks (give or take) to go before then.
Hope that helps. Best of luck!
pendragon!
