Originally Posted by
SantaMonica
35 gph was just done through experimenting. "Less" is not really a savings, because it also slows filtering. Filtering is proportional to wattage, flow, area, and screen roughness. Plus, slow flow blocks more easily, which stops filtering completely.
It's not a good idea to put a 300 or 400 gal tank under the care of a single pump ($100 savings?), or single light, single fuse, etc. Unlike a skimmer, if your only scrubber goes out, you will immediately get a build up of nutrients, and start seeing green coatings on everything in the tank, especially if you have learned to feed heavy (skimmers don't remove nutrients, so when they go out, nothing happens). If you don't want 2 pumps, you can put one of the scrubbers under the overflow.
It's just a matter of time before you'll realize why it was a good to go with 2 separate units.