Working in deep sumps?

[Oberst Hajj]

I'm kicking around the idea of using a 75g or 100g tank to build a sump for the 270g DT I recently ordered.

For those of you that have used such tanks for your sump, is it a PITA to work in it? I would probably only run about 12" of water through it (the skimmer would still have to be raised up) to allow for enough space for the DT draining into it when the pumps are off.

With roughly another 10-11 inches of glass above the water line, does that make it a lot harder to work in?

 

[Saltyreef]

I'm kicking around the idea of using a 75g or 100g tank to build a sump for the 270g DT I recently ordered.

For those of you that have used such tanks for your sump, is it a PITA to work in it? I would probably only run about 12" of water through it (the skimmer would still have to be raised up) to allow for enough space for the DT draining into it when the pumps are off.

With roughly another 10-11 inches of glass above the water line, does that make it a lot harder to work in?

If its a basement sump, no issue.
Under a cabinet and the height of the sump quickly becomes your biggest hurdle when space becomes restricted.

 

[Oberst Hajj]

If its a basement sump, no issue.
Under a cabinet and the height of the sump quickly becomes your biggest hurdle when space becomes restricted.

Good point. My sump will either be under the stand or, depending on how negotiations go with the wife, in a small fish room on the other side of the wall from the tank.

 

[Oberst Hajj]

Well, the negotiations went well and I got the green light to build a 5'x13' fish room on the other side of the tank wall. So now maintenance should be much easier.

 

[Saltyreef]

Well, the negotiations went well and I got the green light to build a 5'x13' fish room on the other side of the tank wall. So now maintenance should be much easier.

 

[Greg P]

How well your tank drains will depend on the height at the bottom of your overflow, what size drains you use, return pump size ...

My sump is remote and is 19" tall. It sits on 1/2" styro and a 1" square tubing base for levelling. Overall it's 20-1/2" with shims, and the bottom of my back box (overflow) is 41"
With 2" drains it works great with the return @ 100%
My first tank drained through the bottom. With the drains at only 27" tall, and 1-1/2", they couldn't keep up with the return pump and I had to throttle it back.

As for working height, I built a skimmer stand and it's baffle is 16" tall. This allows for max sump volume. I am able to perform a 25% WC by pumping water out of the sump without touching the DT.

DT is a 75 and sump is a 4' 60g I custom built. Total system volume is 115g

 

[Greg P]

If you like the idea of doing WCs without touching the display, you'll need at least a 135g sump to take out 100g of water. Est based on how full the sump would be.

I planned my sump based on exact DT volume wet and sump baffles. Then worked backwards with the math to calculate how big the sump should be.

 

[Oberst Hajj]

For a 25% water change out of the sump, my calculations show I need a 100g sump. 270 + 100 = 370 × .25 = 92.5 gallons. With equipment and rocks in the sump, it should probably be a 110g sump really.

 

[Oberst Hajj]

But I was more concerned about how much of a pain It would be to work in the deeper sumps doing maintenance.

 

[Greg P]

But I was more concerned about how much of a pain It would be to work in the deeper sumps doing maintenance.

Yup, got that. Was just pointing out it's helpful to have enough water in the sump to avoid removing DT water.

Now that you have the OK to build a remote sump, height is not an issue for maintenance

 

[Samsquanch]

I was going to use a 55 gallon as a sump for my new 125 but after putting it under my cabinet there was only about 6 inches of space between the top of the sump and the bottom of my DT so that was a no go. Unless you'd have a problem like that I'd say go for it, it never hurts to have the extra water volume and like you already said you'd raise your skimmer up

 

[Oberst Hajj]

Yup, got that. Was just pointing out it's helpful to have enough water in the sump to avoid removing DT water.

Now that you have the OK to build a remote sump, height is not an issue for maintenance

Yep, with the fish room it is no longer a concern. Now I'm just trying to find out how far down in the tank the return and overflow holes are drilled from Planet so I can calculate how much water will siphon back to the sump.