450 Gallon Tank/125 Sump Advice

[ptgb]

450 gallon tank with two overflows, each overflow is 8" w x 16" l x 36" d (=20 gallons each). Sump is a a 125 gallon that has the lower baffles at 12", so if my calculations are correct the sump will hold 72 gallons.

There are four 1" drains (two in each overflow) and four 3/4" returns (two in each overflow).

I plan on running two return pumps (4000 gph max each, but with a 6 ft head, so probably 1/2 the rated gph each) one for each side, that runs one hose and then splits to each return on either side.

Couple questions:

1. How high should I put the drain pipes in the overflows? I was just planning on using open pipe with strainers on each as there are four drains, so I don't have to worry about any major plug-ups. Each drain has a gate valve on it. I was thinking about 18 inches high in the overflow, so with the pumps off, it will drain 20 gallons total (10 from each overflow into the sump). I also want the water decently high in the overflow so I don't get that waterfall effect (sound) as it's in the main living area of the house.

2. How do I go about setting the water level in the sump? Do I fill the tank to the level of the overflow teeth and then fill the sump to the top level of the lower baffles, then add 20 gallons to fill the overflows once the pumps are turned on?

3. Do I start the pumps with the gate valve completely open? closed? The pumps on low/middle/or high?

I have a 90 gallon reef tank with a 20 gallon sump, dialed that in easily and quickly. This huge setup has me nervous as two high power pumps and a ****-ton of water to deal with.

Any advice would be greatly appreciated.

 

[tlindsey]

View attachment 1427580

450 gallon tank with two overflows, each overflow is 8" w x 16" l x 36" d (=20 gallons each). Sump is a a 125 gallon that has the lower baffles at 12", so if my calculations are correct the sump will hold 72 gallons.

There are four 1" drains (two in each overflow) and four 3/4" returns (two in each overflow).

I plan on running two return pumps (4000 gph max each, but with a 6 ft head, so probably 1/2 the rated gph each) one for each side, that runs one hose and then splits to each return on either side.

Couple questions:

1. How high should I put the drain pipes in the overflows? I was just planning on using open pipe with strainers on each as there are four drains, so I don't have to worry about any major plug-ups. Each drain has a gate valve on it. I was thinking about 18 inches high in the overflow, so with the pumps off, it will drain 20 gallons total (10 from each overflow into the sump). I also want the water decently high in the overflow so I don't get that waterfall effect (sound) as it's in the main living area of the house.

2. How do I go about setting the water level in the sump? Do I fill the tank to the level of the overflow teeth and then fill the sump to the top level of the lower baffles, then add 20 gallons to fill the overflows once the pumps are turned on?

3. Do I start the pumps with the gate valve completely open? closed? The pumps on low/middle/or high?

I have a 90 gallon reef tank with a 20 gallon sump, dialed that in easily and quickly. This huge setup has me nervous as two high power pumps and a ****-ton of water to deal with.

Any advice would be greatly appreciated.

twentyleagues
duanes

 

[tlindsey]

A thread on baffleshttps://www.monsterfishkeepers.com/forums/threads/sump-baffles.728967/

 

[Backfromthedead]

I would position the drains right below the overflow weir, so maybe 2-3" below the waterline. Theres no need to place them lower imo.

 

[twentyleagues]

If you want this to run silent look into bean animal overflow design. You have the plumbing to make it work already. They are dead silent. I've always just routed my return over the back of the tank, 3/4 is pretty restrictive and creates more head pressure. I'm not sure why tank manufactures always go there. Maybe trying to "help" you size your return pump?
You would need all the pipes in the overflow to do a bean style anyway. Like Backfromthedead said less the water has to fall into the overflow less noise. But if doing bean the main drain will be a full siphon so to achieve that it will need to be below the surface by quite a bit. Having it lower will cause more water to drain to the sump in a pump off situation. On mine the main siphon is about half way in the overflow. As long as it can't suck air from the surface it will work and be super quiet.

Overflow Boxes and Drain Styles - Durso, Herbie, and Bean Animal

Decide which of the three most common types of drains and overflow boxes is right for you and your tank.

blog.marinedepot.com

Gives a bit of a idea on the styles of over flow. On yours I'd do both 3/4 as emergency drains.

 

[TheWolfman]

Your full syphon stand pipe should be about 6" below the water line in the overflow. Your secondary drain will set the water level in the overflow. I would position that 2" below the teeth of the weir. The gate valves should only be used on the full syphon drains. The secondary drains should be open channel. You don't want anything to slow those down in the event of a blockage on the full syphon and as a result they would be noisy alerting you of a problem. Your first time starting up the pump run the gates wide open. Once the sump is running you will set them and never need to touch them again. The 1" bulkheads in the overflows won't handle that amount of turnover your aiming so expect to be a bit shy of that.