In - Tank Circulation Rates?

[Canadian Man]

Well I am off tommorow but havent organized any rides.Anyway, to stay on topic ;)
I would put the ph's at the surface if you are adding 2. if your returns are near the surface they may provide enough agitation so you could put the mj's a little down but i wouldnt put too much emphisis on it just put them where they will mix the current up the most.