Modular marine overflow questions?

iReefer12 · Dec 24, 2023

I really wouldn’t use the 2nd gate valve. Their not cheap (return and get your money back). It’s just unnecessary and their bulky too.

The only way that open channel pipe goes full siphon is if the Full Siphon drain gets blocked… in that case you want it to be full siphon with no restriction

Contractor_Chris · Dec 24, 2023

I went cheap and bought sch80 ball valves and they came in a 2 pack. One was 38 or amazon had two for 40$. I wasn't ready to blow 100+ dollars per gate valve. And they are worlds easier to adjust then a sch40 ball valve (made that mistake on previous tanks)

iReefer12 · Dec 24, 2023

TBH I’ve never used a ball valve instead of a gate valve… it could work, but it also could be a PITA to make work. Just make sure you have the ability to cut it out and install a gate valve if you need to.

DCR · Dec 24, 2023

Trying to throttle the full siphon with a sticky 1-1/2" ball valve is going to be difficult. I would get the gate valve for the full siphon. If you adjust it properly with just a small trickle going over the open channel overflow it won't be noisy.

Contractor_Chris · Dec 24, 2023

I feel the sch80 ball valves don't stick. They seem smooth as butter esp compared to sch40 ball valves. I agree I wanted to do a gate but 120 dollars is absurd and just highway robbery. Yes I've spent copious amount on everything else thus far. But some reason that's just a pill I can't swallow. Know of anywhere to buy one besides brs for that kind of money?

DCR · Dec 24, 2023

I would also consider swaging down to a 1" gate valve on the full siphon - at least at the gate valve. 1-1/2" is massively oversized for the flow you will have. It will be severely throttled and more difficult to control. Also save so some money.

iReefer12 · Dec 24, 2023

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It’s just how expensive they are. Tough pill, but worth it IMO.

jason2459 · Dec 24, 2023

Contractor_Chris said:
I feel the sch80 ball valves don't stick. They seem smooth as butter esp compared to sch40 ball valves. I agree I wanted to do a gate but 120 dollars is absurd and just highway robbery. Yes I've spent copious amount on everything else thus far. But some reason that's just a pill I can't swallow. Know of anywhere to buy one besides brs for that kind of money?

Sched 80 ball valve. They get sticky

I ran it for many years. I also reduced after it to a 1" that made it easier to dial in and quieter as mentioned above.

I now have a 1" gate valve on my new setup after moving tank locations. I would have done this from the beginning.

Contractor_Chris · Dec 24, 2023

I just dont understand why the over flow box AND trigger sump has 1.5 bulk heads/adapters to just reduce everything down to 1" ‍

at that point i have to return everything i have from brs, pay for shipping back. Get smaller stuff plus buy reducers.

Though on my 300 gal fresh tank I do have a 1" full siphon and a 1¼ durso. And agree it's still throttled down, as the filter sock holder can't handle more flow and just makes a mess and spills over.

Contractor_Chris · Dec 24, 2023

I guess good time to ask, what size return line is everyone running then? ¾ or 1"?

GlassMunky · Dec 24, 2023

Contractor_Chris said:
So I purchased a 3000gph modular marine overflow for my 180 gallon tank. Just installed it. But the two bulk heads going thru the tank are completely in the way of being able to make a durso. The 3 bulk heads going out are 1½" so doing a bean animal. 1 full siphon, one durso, 9ne emergency. But they are right on top of each other. Close enough I'll have to stagger all the unions. I'm sure many have this over flow. Post a photo or explain what you did that worked? Thanks Chris

Make the middle one the emergancy pipe and just a straight piece of tube.
Use the 2 ends for the other drains.
Gives you all the room
On the sides for the durso

DCR · Dec 24, 2023

I use two 1" returns and 1" drains (Bean) on a 150 gallon. It is not a big deal to reduce down. You have a really good overflow box. I think they are just conservative in their sizing. I agree that the ball valve is going to become sticky over time. You can use it initially and modify it later. I understand the feeling of having spent alot of money already.

GlassMunky · Dec 24, 2023

Contractor_Chris said:
I guess good time to ask, what size return line is everyone running then? ¾ or 1"?

1" Full siphon drain. 1.5" durso and 1.5" emergency drain on my 210G with dual 1" return lines (DC return pump only runs at 75%)

billyocean · Dec 24, 2023

Grab a gate valve from flexpvc.com it's like 50 bucks for a 1.5". I have 2 MM 3000 gph overflows on a 300 I am building. As someone mentioned previously you can cut the bulkhead down with a saw and use the "p-trap 90s" on left and right holes and use the straight emergency pipe in the middle. Leave emergency about an inch below the top of the overflow. Even with 2 overflows it's pretty quiet. 7" filter socks silencers helped a lot too.

If you cut the backside of the bulkhead it leaves the room needed.

GlassMunky · Dec 24, 2023

Personally, id ditch the durso for the full drain, its wasted space.
just use one of these for the full siphon.

Low Profile Bulkhead Overflow Strainers - Lifegard

Low profile strainer that extends fractions of an inch past the bulkhead itself. Prevents fish, snails, and other tank inhabitants from getting sucked into your plumbing, sump or pump and subsequent damage. Slip Low Profile Strainer - Used to slip inside of a slip bulkhead Thread Low Profile...

www.bulkreefsupply.com

iReefer12 · Dec 24, 2023

Contractor_Chris said:
I just dont understand why the over flow box AND trigger sump has 1.5 bulk heads/adapters to just reduce everything down to 1" ‍ at that point i have to return everything i have from brs, pay for shipping back. Get smaller stuff plus buy reducers.

Though on my 300 gal fresh tank I do have a 1" full siphon and a 1¼ durso. And agree it's still throttled down, as the filter sock holder can't handle more flow and just makes a mess and spills over.

I think the suggestion is to reduce down to 1” only on the full siphon and only at the gate valve, (overflow box bulkhead 1-1/2” reducer -> 1” gate valve -> reducer going back to 1-1/2” to continue the drain line down to the sump).

The point being that the gate valve on the full siphon is reduced already to control flow. So reducing down to 1” really isn’t compromising anything.

1” return line should work fine for this size tank.

Fungusamongus · Dec 25, 2023

Contractor_Chris said:
I feel the sch80 ball valves don't stick. They seem smooth as butter esp compared to sch40 ball valves. I agree I wanted to do a gate but 120 dollars is absurd and just highway robbery. Yes I've spent copious amount on everything else thus far. But some reason that's just a pill I can't swallow. Know of anywhere to buy one besides brs for that kind of money?

60$ for a gate valve at saltwateraquarium. Unless you need a 2 inch. Totally worth it. Mine is super smoothe.