Nitrate Problem

Question
Hello, I have a 45 gallon freshwater tank.  In this tank I have 4 angelfish, 4 neons, 1 corycat and 1 pleco.  I also have one Amazon sword.  My ph is 7.4, my ammonia and nitrite levels are 0.  My question is what is a good nitrate level for a tank my size.  Currently my nitrate level is 50.  I test it every week and it ranges from about 30 to 80 but it mostly stays closer to 80.  My fish seem fine, but I do have trouble adding fish to my tank.  They seem to have trouble in the beggining (clamped fins/pale) but if they make it through they begin to look healthier.  Right now all of my fish look very healthy (bright, active and flowing fins). I do vacum the gravel and do a water change of about 20% weekly.  Do you know any ways to lower nitrate levels?  Are they hurting my fish? Thank you in advance.

Answer
Hi Brent;

I like nitrates to be at 40 ppm or lower. It is not considered very toxic until it gets over that level. It weakens fish to become ill more easily and prevents them from breeding. More live plants will reduce the nitrates naturally because it is fertilizer for them. Also feed less food. The more waste that goes in there, the more nitrate there will be. Be sure that whatever you feed to the fish is gone in 5 minutes after you feed. None should be leftover anywhere, including the gravel and decorations. Feed once a day. If the plecostamus needs more food, give him vegies. A chunk of squash or romaine will do the trick without adding major polluters like algae wafers or food tablets. They leave lotsa mess to clean up!

I think your water change schedule is fine. Just add more plants and feed less. Nitrates will be fine in no time.

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