Thank you, yes, the DI water in the ATO has ammonium bicarbonate and trisodium phosphate in it.You mean ammonia and phosphate together ? That may grow algae, and is more likely to grow bacteria. Will that happen, I don’t know.
My tank consumes 4 dKH of alkalinity and more than 0.1 mg/L of phosphate every day. I’m having to dose a TSP solution twice daily just to keep phosphate from hitting zero. So it seems easier to add it to the ATO. I’ll report back what I see.