To much powerhead?

I just got my two new powerheads in today 1300 gph so I relocated my older two powerheads to the back wall of my tank which are 800gph but when I started the two new pumps they are disturbing my sand bed and kicking up sand all over the place. I have them facing up and towards the front of the glass.
Any suggestions?

 

less powerheads

 

What size tank?

 

Oh sorry thought I had the info in my sig but its a 75g tank.

 

then all you need is like 1500gph MAX

 

Hmmmmmmm, I have just over 1000gph in my 20g tall and wouldn't be against having some more flow. And that is with a LOT of Zoas and GSP.

I think 1500gph in a 75 would be on the very low side.

 

1500gph (total) is on the low side. It'd have to be 4000gph+ to be considered high flow.

You'll have to play around with them; there will be a way they don't constantly disturb your sandbed. Try angling them differently or more towards the center. Also try pointing them more towards the surface, even if you have to lower them in the tank.

 

ok will do I might just have to lower them cause I have tried different angles from this height level

 

Water movement is important in the reef aquarium with different types of coral requiring different flow rates. At present, many hobbyists advocate a water turnover rate of 10x: 10 x aquarium capacity in gallons = required flow in gallons per hour. This is a general rule with many exceptions. For instance, Mushroom Coral requires little flow and is commonly found in crevices near the base of the reef. Species such as Acropora and Montipora thrive under much more turbulent conditions in the range of 30 to 40 times more flow, which imitates breaking waves in shallow water near the tip of the reef. The directions which water pumps are pointed within an aquarium will have a large effect on flow speeds. Many corals will gradually move themselves to a different area of the tank if the water movement in its current area is not satisfactory.

More information can be found http://en.wikipedia.org/wiki/Reef_aquarium#Water_movement

 

Am I to understand your coral move themselves in your tank?