Hi, I've had my system running for over a year now. It's been doing well. I have a 300 gallon fish tank, two 51X51 media beds, two 51X51 floating raft tanks. Recently my ammonia levels rose to 0.50ppm and the nitrates are 160 or above. Nitrites are 0ppm. I have approximately 50 mature Tilapia in the tank. How do I get that ammonia level down? And is the high Nitrate level a problem?
Build a separate overbuild bio filter ... it will make sure ammonia is converted to nitrates. Need more plants or less fish to get nitrates down ...
Well, tilapia are tough, so I don't think there's any reason to panic (Unless you have fish dying. But even then, I would argue that panicking doesn't do you much good :)). Still, 160ppm nitrates won't necessarily make for happy fish.....
Most fish can go a while without food, so I would stop feeding them until you see your nitrates go down a bit. Also, check for any dead fish or decaying organic matter that could be the culprit of any extra ammonia going into your system. If you can't get things to balance out after that, you can add more plants or make fish tacos.
For nitrates just add more plants to eat them up. The .5 ammonia will not be a problem for your Tilapia but Alex is right on with the cutting back on food. What is the pH?
Thanks guys. I do have some pretty big Tilapia and am still not fully planted again this year. Our daughter got married in June down in Savannah so I kinda didn't plant but half...Was busy on that wedding!! I love the tips you all gave and the humor is always welcome! By the way...My system was featured in the Fall Edition of The Lake Wylie Magazine! I got 3 pages with pictures. The magazine is seen by about 10,000 people!! sherrie
I'm also keeping the PH at about 6.7