Stupid Plumbing Question

[*HOVA*]

I have what’s probably a stupid plumbing question but in all my years one I’ve never dealt with lol

I’m having a 250G tank built which will be the largest I’ve had setup. Traditionally I’ve used a Herbie style plumbing and been pretty happy but I’ve never plumbed more then 1 main drain. In order to achieve the turnover I want on the new tank I will need 2 main drains and of course I will have 1 emergency and 1 return.

My question is how will I fine tune 2 drains? Gate valve on each or 1 wide open and gate valve on 2nd to fine tune?

I’m also not opposed to using a different style such as the Bean Animal but that setup also primarily uses 1 drain so I’m a little stumped on how to setup with 2 main drains....

 

[dan3949]

Either way will work. Essentially, you need a certain flow area (set by the valves on the drain lines) to obtain the desired flow rate draining out of your tank into the sump. This could be accomplished with one large drain line or multiple small drain lines. The drain lines do not need to be set in the same position.

I think it would be easiest to "fine tune" the drain flow rate by running 1 line fully open and using the valve on the other line to "tune" your flow to the desired amount. Although I would not want either valve run more than 15% closed. It is too easy for an opening that small to get blocked. Adjust your "fully open" valve so that the "tuning" valve is around 50% open.

I fully recommend a "Bean Animal" Style overflow (or any other fully submerged drain line). All you need is an open emergency line if your fully submerged lines becomes plugged. I have run a fully submerged drain for almost 10 years and never had a problem. If tank noise is a concern at all, a fully submerged drain is dead silent.

 

[KStatefan]

Why do you need to main drains? Size the main to flow what you need.

 

[*HOVA*]

1 drain running at 100% calculates to only about 5x turnover.

 

[BackToTheReef]

I have what’s probably a stupid plumbing question but in all my years one I’ve never dealt with lol

The only stupid question is the one you don't ask!

 

[schuby]

I have a 150 gallon DT with three 1.5", independent drains from one over-flow box. I use three open pipes in the over-flow box: 1" high(starts siphon faster and quieter), 3" high, and 5" high (6" deep box). My two return pumps push around 600 gal/hr total. I have a valve on the drain connected to the lowest input pipe (1" high). To get a full siphon, the valve is only open 25-30%. The other two drains are not utilized, basically two backups.

You didn't say what throughput your planning or the size of your return pipes, but you may not fully appreciate the volume of water that goes through a drain pipe with a full siphon. I wouldn't be suprised if I could get 2,000+ gal/hr through my primary, 1.5" drain.

Just a note, my overflow is very quiet all the time, with valve set to get full siphon on first drain and not overflow to second drain. I have a cover on my external, overflow box, glass lids on my tank, and a closed hood (with input & output fans on when lights are on). An open-top, no-hood tank may need to use a more traditional animal-bean style to be as quiet.

 

[WVNed]

I have 2 full siphon drains with valves and 2 drains with standpipes drains on my tank.
It works the same as if you only had one.
If you need 1.5 times the flow one drain can handle you can close one valve and leave the other open or close both some.

 

[*HOVA*]

Thanks guys. I’m probably just overthinking it but I like to get it right the first time

 

[JoshH]

1 drain running at 100% calculates to only about 5x turnover.

So you upsize the pipe size to fit the flow you need you'd be surprised how much water a 1.5" drain can handle... on another side note, why the need for more than 5 times turnover? Most would argue 5 times is plenty and maybe even excessive turnover through a sump...

 

[WVNed]

As the potential size of a disaster goes up the need for redundancy goes up.
I have 4 x 1.5 inch drains on my 240. Any 2 of them will handle the flow.

 

[schuby]

@*HOVA* , spill the beans. How much flow, DT-to-sump, are you wanting to achieve on your new 250G tank? What size drain pipes are you planning to use?

I had planned for 10x turnover on my tank, but I get about 5.5x. The pumps and head-pressure that I calculated was way off. I'm very happy with my result. I get additional flow in my DT from powerheads and in my sump from a small powerhead (for my chaeto).

 

[K7BMG]

I agree the stupid question is the unasked one.

There should be GATE valves on all your drains.
This way you can do anything you want.
Typically out of the three.
Primary drain gate should be wide open.
Secondary drain the one used for actual flow control
Third the emergency wide open.

Yes you can use doth drains partially closed to provide equal amount of flow per drain.
But this takes a lot more work to properly adjust.

 

[ChuzUThisDay]

...In order to achieve the turnover I want on the new tank I will need 2 main drains and of course I will have 1 emergency and 1 return.

My question is how will I fine tune 2 drains? Gate valve on each or 1 wide open and gate valve on 2nd to fine tune?

I’m also not opposed to using a different style such as the Bean Animal but that setup also primarily uses 1 drain so I’m a little stumped on how to setup with 2 main drains....

You've got it figured out but don't realize it Having the three drains allows you to run a Bean Animal and yes, one runs at full siphon and the second with a gate valve allows you to tune it while the third acts as an emergency. I ran this on my 125 and will always run the Bean Animal where I can. It's quiet, always starts back up after a power outage, and it's pretty easy to tune.