Overflow question

[mvit]

I have a 29g soon to be mini-reef. I am thinking of adding a sump mainly for extra water capacity and to move the heater and skimmer. Most likly it will be built from a 20long. I have to run an overflow box as the tank is not drilled. If I do this I need a reliable box that won't break siphon and also am considering a float swith in the main tank to kill the return pump if it gets too full. Does this sound do-able?
My return pump should deliver 400 to 500 gpm at 3ft of head. Do you think I will have to throttle/bypass it down?
Does that sound like too much flow for a small tank?

Oh ya, can I run my hang on skimmer in the sump?

This is the overflow I am considering....
http://store.hurricanefilters.com/quprov.html

This is the floatswitch ...
http://www.autotopoff.com/products/ST1/index.htm

Does anyone use these switches or overflows?

Please give me any opinions and input.

Thanks,
Mark

 

[Krish]

The type/style of overflow you are thinking about IMO is one of the most reliable. I use to have one and that thing never broke siphon. The only downfall to them is they take up a bit more space in the tank than an overflow like a CPR would and sometimes you have to mess with them some to quiet them down a bit. Other than that, they are a good choice. As for the skimmer, what type do you have? Most hang on skimmers will work in a sump. You just have to make sure the water level in the sump is high enough for it to function properly. As for a float switch, it may be a good idea to have for extra safety, but not totally necessarily. I don't know of that many people that use them in this case. Most don't without any issues

 

[mvit]

Thanks for the input.
The skimmer is an aqua-c remora with the mj-1200.

 

[dnjan]

Why not drill the tank? I have not heard of anybody who regretted having drilled overflows as opposed to using a siphon box.