150 gallon tall

[poolguy72]

Have a 150 gallon tall reef tank how much flow do I need I have two hydro power heads one 750 and one 1400

 

[uh.oh...]

it depends on the corals you want. Lots of lps and you won't need as much as sps. Or maybe a mixed reef and you'll just have work out the flow. What is the return volume on your tank? I'd go with another 1400, to equalize flow, and point the 750 back at your return outlets. You might need a little more rock too imo.