plumbing and straining in sump question

[warrenmichaels]

I'm building a sump from a 20 gal long. I'm planning to have two inputs (main and overflow), one output, and an external pump. It will be three chambers, with the first being a refugium with chaeto, the second being for the skimmer, and the third being a return.

For the inputs, I'm planning to have both of them plumbed to the bottom of the tank. Each will be at either end. The main input will be connected to an "L" that directs the flow to the lengthwise horizontal center of the refugium, then directs the flow at 90 degrees to travel across the refugium widthwise.

The output will be at roughly the same height as the external pump. Since I'll have 7" of head in the return chamber, it won't be an issue, will it?

Finally, as needed, I'm thinking of hooking a filter floss strainer to the return bulkhead inside the display tank. It will be hooked up for a few hours a week when I'm cleaning the tank, just to catch debris.

Is there any reason why any of these three ideas won't work?

Thanks

 

[warrenmichaels]

Also, how much flow can chaeto tolerate? Will too much flow shred it?

 

[billdogg]

How big is the DT? 20g is a pretty small sump, and you have a lot planned for such a little space. Chaeto prefers enough flow to get it to tumble some

 

[warrenmichaels]

90 gal. I think I'll use something other than chaeto. Maybe I should go larger.

 

[Vinny Kreyling]

You have to remember-- most sumps operate around the 1/2 full mark.
So while you have a 20 gallon sump there is only around 10 - 12 gallons of water there

 

[laverda]

I would not even bother with a 20 gallon sump on a 90 gallon tank. Your not going to be able to get enough flow through it without bubbles being a big problem. I would also be concerned about using an external pump plumbed to a bulkhead in glass as thin as used on a 20 gallon tank. Most external pumps are to much flow for a 20 gallon sump. Your not going to have enough room for cheeto to even be effective. Get the biggest sump you can fit under your stand. Using an internal pump will give you more room and less risk of leaks. You only need 400-500 GPH flow through your sump, so the pump will not take up much room. If you use a good quality energy efficient return pump you should not be adding significant heat to your system.
It makes much more sense to have your filter floss in the sump before your cheeto and skimmer. Otherwise your going to get a lot of debris settling out in your sump.