I have a twenty gallon aquarium with four medium goldfish in it. I've been regimentally chaning 20% of the water every three to four days and by and large my fish have been fine. I went on vacation this weekend, and before I went I changed about 20% of the water just to be on the safe side.

When I came home on sunday evening, I noticed that one of my fish (the smallest, actually) had started habitually lying in the substrate with clamped fins. I immediately became worried and wondered if he could be sick. The other larger goldfish were still sporting about like they were at a party, so they seemed fine. Since my small black moor showed no outward signs of illness other than hiding out at the bottom, I was worried that it might be water quality, so I tested the water and the Nitrites were off the scale (my test kit gives me a reading at 10 x_x. I was seriously disturbed by this, so I changed out another 25% of the water at around noon and then tested again about an hour later. Still off the scale, so I changed out another 25% at around four, and then tested again and it was still off the scale. Finally, at around three in the morning, I changed out another 25% and dosed the water with AmQuel+ which promises to help neutralize Nitrites. I tested the water a few minutes ago, and while the test still came out as off the scale, it came off as less off the scale (not so colorful a reading on my test strip) All the other readings are under control now (pH 7.1, Alkalinity 80, Hardness 120, Nitrate 20) but the Nitites remain at at least 10.0 (which is as high as my scale goes, in fact, now I'd say that theyr'e actually down to 10.0, and they were considerably higher before).

My tank has been running since the beginning of August and has had a TopFin Power Filter 20 on it since then, along with an undergravel filter for a 20 gallon aquarium. I've had another problem with the aquarium and I wonder if it's related to the spiking Nitrite problem. The water has been a perpetually milky cloudy white since I started the tank. At first, I figured that this was a beneficial bacteria bloom to help my beginning cycle, but after about a week I dosed the water with the perscribed amount of Proquatics Water Clarifier. This did litter. I continued to to this about once a week for the next three weeks, and the water still didn't clear. Wondering now if my cheap TopFin filter just wasn't doing its job properly, I went to the store and invested in an Emperor 280 with a biowheel, figuring, well my fish only need one powerfilter, so they might as well get a good one. Hoping to clear the water, I installed this filter last night along with my smaller TopFin twenty, which I plan to move to a starter spawning/hospital tank a little later this month. I was also worried that the ProQuatics Water Clarifier wasn't doing it's job, so I invested in a bottle of Bright n' Clear and dosed up the water after I had finished my final bit of the 75% change. The water remains milky cloudy with little tiny bits floating in it, despite my rigorous substrate vaccuuming, excellent filtration, and good waterflow. Since I can't figure out what's making the water so yucky looking, I was wondering if it could possibly be my Under Gravel filter, since a lot of the aquariusts here don't seem too keen on them. My filter is properly aerated, it has an Elite799 running just the aeration on the uplift tubes, while a larger AirTech 2K2 is running the tanks aeration through the airstones. I can partially see under the tank, so I know that there's /something/ living under under my Under Gravel filter, I just don't know what. Also, since I do have an Emperor 280 now, I understand I can do away with the Under Gravel Filter period, yes? Because the Emperor fuctions as a biological filter as well. Nitrite problems aside, would the lack of an Under Gravel fitler improve the lives of my fish?

In any case, concerning the Nitrite problems, do they come under heel as slowly as this? Should I continue three 25% changes a day (dosed with Aquarium Salt to relieve my little black moor's stress) or should I be doing something differently? Has my bacteria cycle hit a dead end and that's why there was such a spike in Nitrites? Should I be doing something to help reestablish my cycle at the same time as bringing the Nitrites under control? Should I continue to dose with AmQuel+, or should I leave the natural changes of the water to take care of that? Is it safe for the fish to continue huge 75% changes of water, provided they're done in stages? Is the cloudy water problem related to the Nitrite spike or vice versa?

I'm very worried about my fish and doing everything in my power to help restore the balance to their water, and now I'm kicking myself on getting lazy about testing the water twice a week.

One final note, around the first week of August, the tank claimed the lives of the five small feeder fish in it. They came from the petstore sick and died of Ich quite shortly. I dosed the water with Mardel CopeprSafe to make sure that none of the waterborne parasite could survive long. One month later, with healthy fish, could this still be a partial cause of the cloudy water?

My Black Moor is in your hands, ladies and gentlemen.

If there's a lot of gunk underneath the filter plate, that could very well be contributing to your cloudy water. Unlike many here who are emphatically anti-UGF, I have used them for years with no problems, and actually see great benefit in their use so far as biological filtration is concerned. It is just like any other filter, though, it needs to be maintained (cleaned beneath the filter plate), and if the fishkeeper is unwilling to do that then certainly it does have the capacity to cause problems. Filters with biowheels are great at biological filtration, though, so now that you've added the emporer, you may want to eliminate the UGF just for ease of maintenance. Be sure to remove your fish from the tank before removing the filter plate so they aren't subject to the bloom of gunk that has accumulated underneath.

The poor water quality (high nitrites) could be a cause of the cloudy water as well. Sometimes eternal nitrite spikes are due to there not being enough biological filtration in the tank. Also test your tap water to be sure they aren't coming in with that. Nitrites are very difficult to lower through water changes alone. Changing a large amount of the water (as much as you want, just be sure incoming water is the same pH and temp) may help temporarily, but usually if there is a real problem, the levels will rise again quickly. Add 1 1/2 T of salt for every 5 gallons. This will help protect your fish from the effects of nitrites until you can get them under control.

After a little reflection, I realize that I may have killed my beneficial bacteria colony on my first filter by rinsing it under tapwater that had not been treated for Chlomines. I am now dosing with the salt and my black moor seems much happier, although his fins are still largely clamped. I think I may shelve this undergravel filter for a while, until I set up a second tank where I'll probably give it a whirl again. Also, all the goldfish books I'ev researched (The Essential Goldfish and then The Goldfish from Howell Book House) suggest you have one to two inches of substrate over the UGF. Here I've seen no more than a quarter of an inch or the bacteria might go anerobic or some other complication. I'm going to try and restablish the cycle with some beneficial bacteria, and keep the fish in the salt until I can reduce the Nitrites.

Since my first post, I changed out another 25% of the water, and the Nitrites are still very high (still at 10.0 ppm). I guess all I can do is try to restablish the cycle. Would you suggest waiting to removed the UGF until I had stabalized the Nitrites, or removing immediately?

I also tested the tap water, and that's not the source (if only it were that simple!) and the pH is always a steady 7.0.

I was also thinking, since I'm worried that I've killed off my bacteria colony, would investing in some BioSpira help to beef it up? I had no idea products like Cycle were useless ^^; I guess you learn something new every day.

The good news is that I've added some BioSpira and my Nitrate cycle seems to be going full swing again. I did another 25% water change earlier today when I noted that Nitrates were helpfully going back up. Hopefully the good bacteria along with the daily water changes will help me get the Nitrites back under control ^_^.

If you do not have an UGF, it is a good idea to keep the gravel to a minimum, but with an UGF in the tank, water (and air) is continually being pulled through the gravel. Since with an UGF the gravel itself acts as the filter media, it is a good idea to have a couple inches of gravel on top of the plate.

Normally I would suggest you wait until the cycle is complete before removing the UGF, but since you have the BioSpira you could probably remove it now if you wanted. You might want to keep some of the gravel in the tank, though (at least for awhile while your filter stabalizes), since it likely has lots of good bacteria starting to colonize.

Happy cycling!