basic water flow question

I have a mag 1200 for my return and then two Vortech MP40w's that put out 3000 each. You have to take in to account the amount of height you are going up with you plumbing, elbows, check valves etc.. so my 1200 may only be flowing around 900? I would go alttile bigger then what you think you need. I wish I would have gone bigger on the return pump. just my two cents..

 

ok,

if that water going to the sump is gravity fed out of the tank in one (or two?) pipes, wouldn't any fish be sucked/plastered against the intake?

I apologize if that's a stupid question. frogdog

 

If you just have a open drain in the tank, yes things would get sucked into the plumbing. Reef tanks that are 'reef ready' have built-in weir or overflow solutions to this problem - basically a large longitudinal slotted intake for the drain pipe, to reduce the suction of the outflow by distributing it over space and also to prevent unwanted riders with the slots. Non-reef-ready tanks can be fixed up either by modifying them with drilled holes and home-made overflows, or more easily with hang-on overflow boxes.

Do you have Bob Fenner's "Conscientious Marine Aquarist" - it's an excellent book to get the basics down before starting your first tank. First half of the book is all about hardware, water&salt basics, etc.

 

I don't know where many get their information from but with any reef ready tank unless its custom there is no way in hell you will ever push 10x the 200 GPH through the sump let alone 20x's 200 The Pipes could never handle it .. 2. 1" bulkhead will deliver on average 500 to 600 GPH the way the average aquarium is set up and then when all go to the super Dave stand pipe that drops off as the tee and restricted venting really hold the flows back..
Most tank designers and skimmer designers figure the flows at 4 to maybe 5 x's as optimum..
I Run right at 900 to 950 GPh through my sump. 20x200 is 4,000 gph LOL thats lots of water or draining a Olympic size pool every 10 hrs LOL not through a dual set of 1" pipes a 4" water rid drain would have a problem .. you want to move about 1000 GPH through the sump then for internal circulation all you want..
The skimmer needs some dwell time on the water.. I guess they just don't understand fixture unit calculations

 

thanks, Tangster. So if the pipes can't handle it, and the reef ready tanks aren't designed for it, then how do *you* move 900 GPH through your sump? I mean this is the bottom line for me, and where I have a mental block. I have shelves full of books on SW, and I've read every one of them, I just can't understand how you move that much water through the sump............