68 Gallon Rimless Reef Build

[intarsiabox]

Originally Posted by zhasan

What I don't know about is how much water will actually be in the return area constantly when the system is running... is there a way for me to figure that out before setting everything up?

If you are using your ATO then the level in the return section should remain pretty constant as this is the only chamber that fluctuates due to evap. (your ATO water will also go into the return chamber).The level will be what ever you set it at by filling the tank with water until it is all filled to your liking.

Assuming your sump tank is 12" and your baffles remain at 10" high you will have about 6 1/2 to 7 gallons of room for your display water to drain into the sump before it over flows.

To calculate how much water will flow from the DT to the sump when the return pump is off measure from the top of the water column down to where the siphon break would be to get your height measuremnet in inches. Now measure the length and width of the tank in inches. L x W x H to get volume in cubic inches and then divide this number by 231 to get gallons.

[gregzz4]

Besides the good advice given while I was writing this letter

What I don't know about is how much water will actually be in the return area constantly when the system is running... is there a way for me to figure that out before setting everything up?

You set the level in the return area yourself. Enough to keep the return pump from sucking air right before the ATO tops it off is enough to keep the system running. While this isn't an ideal situation, it will give you an idea of how much room you have for powerouts

If I have to increase my return chamber size the only way thats possible is if I reduce the size of the refugium. I don't know what the best or at least minimum size of refugium I'd need on my system. Or is it best to go as big as you can?

If you were to run only chaeto, you could go anywhere from 8 to 12 inches cubed. You want to run a DSB and I have no experience with them, so someone else will have to help you here

I really like how you did your sump. Very well planned out! unfortunately I don't have a lot of realestate to play with here.

Thanks, but I reconfigured it 4 times, so not so well planned out
I built, then tested, then re-built etc

I see you have a 16" tall tank. I suggest you use as much of that height as you can. You'll need to build a stand for your skimmer, but ...
You'll increase your return area by 2g or so, depending on the height of your baffles. This may be all the powerout room you need. Plus, this will increase your total system volume
Hopefully others with a sump similar to yours will chime in ...

What I did was decide what skimmer I'd want to buy in the future and made that chamber as narrow as possible. I also built it as high as possible
I didn't plan on a DSB, so I built a small hang-inside tank for chaeto (later I built it remote). This allowed me to have it be part of the return area which freed up lots of extra volume for powerouts and total return chamber size