[PufferDad]

I have 2 Rio 1100's, each stated to deliver 1450 LPH, situated on back of 150g tank at approx. 4 inches difference in height with the upper head approx. 9 inches from water surface. The tank has two column overflows. I have the heads directed more towards front and center of the tank.

I have had the tank up for nearly 2 months with about 160 lbs live rock, with a couple damsels, crabs and snails...no corals yet.

My question is do these two heads produce enough water movement?

Should the head heights be changed?

What is the rule of thumb if I wanted low, moderate, or high water movement?

I would think the way I have the heads placed is that I have high movement near the headsand front glass and low near front and center of tank.

Has anyone placed their powerheads on the same end and go for clockwise or counterclockwise water movement? Any benefits positioning this way?

Additional powerheads?

I have read since purchasing them that the Rios do not take well with a wave maker cycling off/on.

Discussion please...

[Reefland]

Hi PufferDad,

The general rule of thumb is ten times turnover of the total tank volume per hour. To me, this seems a little light though, especially for SPS tanks. So for a general rule, you really have to go on your own and decide if your flow is adequate based on waste build-up in dead spots. Additionally flow volumes can be decieving based on velocity. 2000 gallons per hour of water movement throughout the entire display is much better than 3000 gallons per hour in a stream 2" in diameter. This is what has made the Tunze Streams and other similar pumps so popular is that their path of distribution is so much wider than traditional powerheads.