Newbie Sump Question

[Zerj]

I have a All Glass 90 Gallon Tank that I will be setting up with a 20 Gallon Sump very shortly. I currently have 2 questions

1. I happen to already have laying around a 20Long and a 20High tanks that could be used for the sump Which would You choose and why?

2. How much water drains into the sump when the pump is turned off on this tank? I was thinking this would affect my choice of sump tanks. If it is 15 Gallons I would definately choose the 20 High to keep the water in the sump deeper and probably quieter


-zerj

 

[Chaser]

Welcome to the board!

I would choose the 20 high because of its smaller footprint. For me, space is always at a premium in the stand.

As for the amount of water that would drain, it would depend on how low the water intake is in your tank (if I understand your set-up). It's important to figure that in when planning your sump. You can also use an anti-siphon hole if your set-up allows. Using 1-way valves on return lines in controversial, but can also work.

Good luck.

 

[waterloomarc]

I would have to agree that in choosing which tank to use that it is mainly a function of space. If you have a lot of vertical room in your stand (assuming going in stand) I would definitely go with the high as it would leave more room in the rest of the stand. But if your stand is shorter (less the 36" tall) I would go with the 20 long as it will make it easier to work in the sump.

-Marc

 

[esmithiii]

Zerj,

Welcome.

To calculate the number of gallons needed for when the power goes out and the tank empties into the sump, use the following:

L X W X D / 230

Where L is the length of your tank in inches
W is the width in inches and
D is the distance from the water line when your pumps are running to the lowest siphon hole or overflow. This will give you the additional gallons that will flow into the sump when the power is cut. Example:

suppose your 75G measures (LxWxH) 48" X 18" X 18" and suppose that your lowest siphon hole is 1" below the surface of the water, (a siphon hole is a small hole you drill in your return line near the surface so when the power gets shut off you don't drain the whole tank into the sump) and that your overflow is 2" below the surface of the water.

48 x 18 x 2 / 230 = 7.5 gallons

So this means, that if your sump is 20 gallons, and when the tank is running it is half full, when the power cuts off, an additional 7.5 (let's say 8) gallons will flow into your sump which would then have 18 gallons in it.