Powerhead

[wrongmove]

I have a 29gallon tank with some Mushrooms, Leathers and Zoo's. The fish I have are- Banggai Cardinal, Yellow Watchman Goby and a Firefish. My question is at what rate of gph do I need a powerhead to keep decent flow but not slam my fish into the glass? Any suggestions will be greatly appreciated.
Thanks,

 

[hatessushi]

It should be 10 to 15 times your water volume of the tank per hour. So in your case if we round you our to 30 gal time 10 would be 300gph at least.