My swords and A. Undlatus are doing the same thing also. I suspect the loaches, but I don't think thats the problem. Are you dosing NPK at all? Don't trust the test kits unless you have a standard to confirm their accuracy. Umm....maybe lets try upping the NO3 first. My 120 gallon is at 1.6 wpg with pressurized CO2 and I'm adding 15ppm of NO3 3xWeek. I'll try going to 20 ppm and see what happens. You may also want to think about your Ca and Mg levels since you have very soft water. You're using excel! Vals don't last long in tanks with excel. I'm not sure why. I just know that they will eventually die.

Also, on my 120 gallon I change 80 gallons of water at a time with no ill effects on the fish. I guess it may depend on what species you keeping, but my apisto's don't seem to mind.


Thanks,
Creighton