Large water changes input

[sirruckus]

90 gallon reef tank with one corner overflow & opposite side return, (2) 950 gph powerheads. Estimate 75lbs Live rock with fine sand bed.

-estimate 30 gallon multi chamber sump with:
-Marineland Pro 300 skimmer first chamber with return line - no filter sock
-one free chamber with heater and sensors
-Sedra 7000 return pump in last chamber with nano sized powerhead to keep circulation in sump & ehiem canister filter acting as a reactor filled with the red ceramic balls, introduced this when trying to seed zeobak

P.H. around 8.2
Temprature 80.5-81.5
Magnesium 1100ppm-1300ppm

I'll get my other readings when I'm at home tonight