What Mag # should I get.

My sump is rated for 400 GPH. I have a 75 gal. tank. I was thinking Mag5 or Mag7. At three feet for the Mag5 is 380GPH and Mag7 and three feet is 500GPH. What do you think. I will be purchasing a pump soon and also power heads for circulation. What power heads do you guys use and perfer? How many should I have in my tank?

Thanks, Eric

 

7 I bought one of those and OMG is pumps!!!!!plus if you use a ball valve you can regulate the flow
http://www.blingo.com/image?h=297&i...MykFCiWqZk3Q3bvIlS356O6ZEdfkhKUc&tw=128&w=350

powerheads...Koralia 4, two of them. maybe one 3 and one 4......

 

Head Pressure:

Every vertical foot=1ft head pressure
Every 3 horizontal feet=1ft. head pressure
Every 90degree bend =1.5 ft. head pressure.
This will effect the total pumping volume, it is easier to get an oversized pump & tone it back with a ball valve

 

i'm using Korallia 2 #3s and 1#4 in my 75, it provides pretty good flow

 

I have 2 K-3s with 400GPH return and two other PH giving 600GPH between the two for 2600GPH in my 75g. I am going to increase it here shortly. I would aim for about 3200GPH.