powerheads or air stones?

[vince]

I am planning to get 4 or 5 powerheads because I want to put some anemones in my 75 gallon tank but can these powerheads act like air stones too? Or do they only control the direction/power of currents?

 

[broomer5]

Many of the powerheads available come with an optional venturi type set up where you can attach some airline tubing. The other end of the tubing then extends up out of the tank water, and the powerhead sucks in air and blasts out a mixture of air bubbles and water.
I don't think it's to good of an idea to do this on salt tanks, although some people do.
It puts a LOT of bubbles in the tank, leads to a LOT of saltcreep, and it's makes noise.
Not to mention what it may do to the fish and inverts.
I do use this setup when mixing saltwater, and it airates/circulates the water nicely in the bucket.
You can point a powerhead or 2 towards the top water level to create some ripples and this will certainly aid in CO2 and O2 gas exhange.
HTH - Brian

 

[vince]

Thanks for the wonderful advice!