How many things can go in a ATO?

[Propane]

I was wondering how many things can go into my ATO. Right now I’m dosing ammonium, magnesium,AFR and occasionally phosphate. My ATO uses about 500ml a day and the only thing I’ve put in there is the mag. Would I be able to put those in it and any other things I dose or is it best left to one chemical.

 

[Randy Holmes-Farley Verified Community Expert]

You can put more than one thing in an ATO, but some things are best not diluted (AFR is one) and some cannot combine (phosphate cannot combine with magnesium or calcium, for example)

Ammonium and magnesium can go in together, but ammonia in a level controlled ato might not be best. Any issue lowering water level might result in ammonia overdose and tox.

 

[exnisstech]

The only thing I have ever added to an ATO reservoir was kalk. Even that got to inconsistent with varying evap rates that I put it on a doser.