submersible pump help

[dneffy]

I recently upgraded from my 40 gallon to a 75 gallon tank. Well I got a great deal on the 75gallon tank with stand, and a AGA MEGAFLOW Sump Filtration MODEL # 2. My question was how many gph do i need in order to run the sump, without it sucking out or not enough water? We just got new carpet in, (stupid hurricaine IKE!!!) so i don't need any floods!
Also I wanted to get you two cents, on wet/dry systems on reef tanks. Is it worth it, or should I convert it to a refugium. Either way I would like your input and what types of pumps you would recommend.

 

[natclanwy]

What kind of overflow do you have?
If your tank has an internal overflow the size of pump doesn't matter so much, you can use any size pump as long as you don't exceed the rating for the overflow after you calculate head-loss. A HOB style overflow is a little more finicky about pump size, you need a pump that after head-loss is calculated is able to move between 70% and 100% of the overflows rating. The most common mistake when using a HOB overflow is using a pump that is too small causing air bubbles to accumulate in the u-tube and stopping the siphon.
I use both pentair quiet one pumps and a mag pumps both seem to be good.
Wet drys do work but require a fair amount of maintence to keep them from becoming a nitrate factory. A refugium works just as good but requires very little maintence to keep it healthy. So a refugium would be my choice but I'm kinda lazy.

 

[dneffy]

It's a internal overflow. It's a AGA Megaflow. Hope that helps.

 

[natclanwy]

Then you can use any size pump up to the rating on the overflow. If it is single 1" drain a quiet one 4000 or mag 9.5 would be a good choice depending on how much head pressure you will have.

 

[dneffy]

Sweet! The Mag 9.5 is the main pump I was looking at. Thanks for the help!

 

[b0b82]

A Mag 9 might be on the small size for a 75 gal tank. What do you want to keep in it? I use a Mag 18 for a return and a Mag 12 for my can.I don't have many fish but I do have some coral.

 

[natclanwy]

You definitely don't need to run that much flow through your sump a mag 9.5 is way more than enough flow you could actually go smaller with no ill effects. If you are trying to get more circulation in your DT you are better off using additional power heads or setting up a closed loop system which is far more efficient than using your return pump from your sump. With the mag 9.5 you will be running the volume of your display through your sump 10x per hour there really isn't much to gain by running it through your sump 15x or 20x per hour.