I am not sure what you mean by separate. I am saying for 4 pumps in a tank use 2 masters each with a slave.
You have a master on each end with it's slave on the other end.
Or each end is a master/slave set.
You could just buy Ecotech pumps that will do exactly what you want. They just cost 8 to 10 times as much.
A small warning. When you get wave trains from 2 sets of pumps going in one tank they will be of slightly different frequencies.
(gee Ned WTH does that mean)
So each set of pumps puts out pulses. One set is slightly faster because you are setting them with a knob. So over time the pulses from each set of pumps in the tank will go in and out of phase.
When they go into phase the pulses add. May make big waves
When they go out they subtract. Looks like pumps are too low
And the point of all that is you can get standing waves that come and go out of nowhere. Or a few unusual waves now and then. These sometimes are much bigger than you want and put water on the floor.
Like this.
and this may not happen. It depends on how much the pulses are damped by the aquascape, how big the pumps are in relation to the tank and the frequency at which standing waves will form in the tank.
Mostly that is just an interesting possibility. If the 2 pump groups are set to almost the same pulse speed it happens very slowly. There are 4 different pulse frequencies in the graph. From pump group 1, pump group 2, the resultant addition shown as the fine waves in pink and the overall shape of the pink is the 4th. It's only messy if one of the pink ones is the same as needed for a standing wave in the tank. A magically appearing wave that sloshes over the side of the tank.
Gee I am less than perfect. Typed all this last night but never hit post.
You are doing a 75? I have 2 SOW-30s in the one in the fish room. They seem sufficient.
