RO Waste Water

[reiverix]

I recently set up an RO unit for my reef tank but I dislike the fact that about three quarters of the water comes out as waste. I was thinking about using this waste water for my water changes on my planted tanks. In Columbus the tapwater is devoid of most things except phosphate. I tested the waste water for a few things and here's the result.

PO4 2.5 - 3ppm
KH 2.5
GH 8
NO3 20 - 30ppm

There's usually no nitrates in our tapwater but recently there was a large spike which seems to be going down slowly. Our water supplier strips out a lot of elements such as iron, copper, calcium, magnesium, etc.

Should I chance it?

 

[Vladimir Zhurov]

Re: RO Waste Water

PO4 2.5 - 3ppm
KH 2.5
GH 8
NO3 20 - 30ppm

Should I chance it?

Looks like a pretty fine water after everything was dosed in "EI for high-light tank" ammounts.

My personal concern would not be nutrients but that something potentially toxic has increased its concentration. But if you say that volume decrease is only 25% (25% goes to pure H2O and the rest is accumulated in remaining 75% of mineralized water) than concentration will grow only by 1/3.

I would give it a try on some test tank.

Regards.

Vladimir.