Nitrate Reductor Question

[HarleyK]

BTW: I, too, have a piranha tank. You say you reach 60 ppm nitrates with 2x/week water changes, which tells me your Ps are still juveniles or you severely limit food for them. My nitrates (in a planted tank) exceeded that by far.... ... until I installed a drip.

 

[Pomatomus]

IMO 60ppm of nitrates and 2 water changes per month doesn't really sound so bad for a FW tank, assuming it's a stable number. Once it starts going over 100 I would start to consider using money to intervene. There is always room for improvement, but those conditions are not very detrimental compared to the spectrum of tanks I've encountered. I guess it also depends how much money you can afford to sink into your setup.