Well said fish_4_all... and if I may just add something I noticed thru this thread... when speaking in terms of nitrate levels, it is true that most fish can adjust to it slowly over a long period of time, but, this does not mean that it isn't causing damage. I could list so many problems caused by high nitrate levels, but the worst and ultimate is an early death for the fish. We see what happens to them on the outside, but most people don't ever get the chance to see the internal damage that is caused by something as simple as high nitrate levels, and it is truly devastating.
As was just said, it's time to deal with the issue at hand, the fish are there and the important thing is to prevent suffering and death. It's good that you are already shopping for a larger tank, I would suggest going as large as is possible, or plan to increase the size again after a period of time.
The angelfish should be fine at the current pH, but the
Discus will not, so you'll want to monitor the pH, KH, and GH in the tank with the
Discus. Add lots and lots of decorations to the tank, this will help prevent stress (which causes illness quickly). If your tap water is over 7.0 for pH, you may need to use bottled RO water which can be purchased at the grocery store and at some pet stores.
Small, frequent water changes (no more than 25% at a time) are the best thing you could do for both tanks, keeping the water quality as stable as can be. When doing the water changes, change just water, don't touch the gravel or filter media. This is where your bacteria will culture most, and the faster the bacteria cultures, the faster you'll get through your cycling. Products like "Cycle" and "Biozyme" both work well, and could be a big help to you right now. I would suggest dosing with one of those after each water change.
Go easy on the food at this point, as that will also raise ammonia levels. Every other day what the fish can
finish in 1 - 2 minutes is all they should be getting right now, until the cycle is complete and the tank is stable. Then, especially with the
Discus, I would suggest feeding once/day (
Discus twice/day), with regular water changes to keep the waste in check.
While the fish aren't going to grow huge overnight, they will grow fast if the water conditions and food are all in check. To buy a bit of time until the larger tank is an option, gradually increase water changes. If you start out with once/wk after cycling, do water testing at least twice/month to see when your nitrate levels begin to increase. When you notice an increase, then do the same with water changes... same amount of water at a time, but twice/wk instead of once. You will find soon enough that the changes will need to be done daily to keep up with the waste levels, and eventually, after that, comes changes every day and healthy fish that are too large to turn around or function in a tank that is too small. This
CAN be done if you take the time for all of the little details that will be so important, but I have to agree with the others here, this is not going to be an "easy" thing to pull off.
Lastly, we're here to help, so as you go through this, please don't feel alone. Ask all of the questions you need and/or want to, we'll do our best to see you through this as safely as possible. I would suggest some reading... not just internet research, but a published book, especially about the
Discus. If you need titles/authors, let me know and I can suggest a few good ones. Knowledge is power, and always remember... the only stupid question is the one not asked.
Best of Luck to you and your fish!
Similar Threads 
