Which overlfow / return pump combination for new 200g system

[Slayer311]

Helping a friend plan out his new 200gallon tank, it is a non drilled tank and not reef ready and he does not want to drill it, so looking at HOB overflows, I will be using Eshops overflows, but wondering which overflows should be used, 2x 800gph? 2x 1200gph? and which return pump would be needed for lets say iwaki / danner

 

[MatthewLaw]

The overflow rate will be affected by the return pump's rate of return.

I am using an eshopps 800 on my 50g tank and have had a lot of positive experiences.

I usually prefer to have the extra margin so maybe 2 1200s, BUT you would need a strong enough return pump to keep both of those siphons active (if not active enough then bubbles start forming in U-tube....). that strong enough return might cause excessive bubbles and an 'excessively strong powerhead.'

I have also been told that the flow through the sump should be 4x the tank size which would be 800gph for effective filtration, so putting a 2000+gph return might be way too strong and adversely affect filtration....

All just my simple analysis and opinion