PVC Plumbing help!

[Heelfiend]

I am setting up my first tank with a sump and need some plumbing help. What I have is two holes in the bottom of my tank inside an overflow box. One is the 1.5" drain and one is the 1" return. I am not using an emergency drain because the area in my sump with the return pump is small enough for the tank to hold that water as well in case of drain failure.

Anyways, I have schedule 80 threaded bulkheads and the plumbing is confusing the crap out of me. I want to put ball valves on both the drain and return for calibration of a silent overflow. I am confused as to if I should use all threaded or switch to slip after the bulkhead. Should I used flexible line after the ball valve? Do I need unions in there somewhere as well? Can schedule 40 work with the schedule 80 bulkheads that I have (as schedule 80 is not at local stores)?

Thanks in advance and appreciate any and all input.

 

[julie180]

My personal experience has been that making the lines on the overflow equal size will run equally.
I did the ball valve thing first and ended up cutting them out because of the noise they made. Anytime you cause friction or resistance, there will be noise.
Slip/threaded is a personal choice. I don't think it matters either way.
Flex or hard pvc, again a choice. If you can make easy bends and avoid 90's the flex is easy to work with if you put it into the oven for a few minutes at the lowest setting.
Good luck

 

[thegrun]

The problem with not having an emergency drain is that you really shouldn't use a valve on a single drain system. If you were to use a valve to make the drain quiet you risk that any obstruction in the drain line will the display tank to flood. One option would be to drill an emergency drain hole in the back pannel inside the overflow box.
As to your questions:
If the area at the bulkhead is accessable I would place a short threaded nipple on the bulkhead followed by a threaded valve and the a threaded barb fitting and use flex tube from there to the pump or termination of the drain line. Schedule 40 fittings will fit into schedule 80 fittings.

 

[Heelfiend]

Why no valve on a single drain system? The return is 1" PVC and the drain is 1.5" PVC. I am worried the 1.5" PVC will drain the tank quicker than the pump will pump the water back into the display tank. The pump is rated at 951GPH (Sicce Syncra Silent 4.0).

I don't think I risk a flood because the area in the sump where the return pump will be is about 10 gallons and the area over the overflow in the 120g equates to about 15-20 gallons. At worst, the pump is dry heaving, right?

 

[Terefel]

Why no valve on a single drain system? The return is 1" PVC and the drain is 1.5" PVC. I am worried the 1.5" PVC will drain the tank quicker than the pump will pump the water back into the display tank. The pump is rated at 951GPH (Sicce Syncra Silent 4.0).

If the drain pipe is draining from the DT anything more than what the return pump is putting into the DT, then something isn't set up right...

 

[Heelfiend]

If the drain pipe is draining from the DT anything more than what the return pump is putting into the DT, then something isn't set up right...

Well that's why I'm here, so I get everything set up right the first time...

Is the setup of 1.5" drain with a 1" return a problem?

 

[thegrun]

The purpose of the valve on the drain line is to reduce flow so the drain pipe will fill up with water almost up to the top of the drain. This eliminates the waterfall noise, but reducing the flow to that degree makes it possible for an obstruction (like a piece of hair algae) to block the flow to the point where your display tank will overflow and flood the room.

 

[Heelfiend]

The purpose of the valve on the drain line is to reduce flow so the drain pipe will fill up with water almost up to the top of the drain. This eliminates the waterfall noise, but reducing the flow to that degree makes it possible for an obstruction (like a piece of hair algae) to block the flow to the point where your display tank will overflow and flood the room.

Right, but like I said the chamber inside of the sump that will have the return pump in it is ~ 10 gallons of water. If ALL of that water were to flow into the tank due to the single drain being clogged it still would not flood the tank. In fact I'd have space for an extra 10 gallons or so even after that.

 

[Uncle Salty 05]

If the sump runs dry your pump will overheat and possibly start a fire, at the very least you will have to replace your pump and possibly all of your livestock.
You should never restrict a drain line.
If your pump is too big you can restrict your return, but not your drain.

 

[thegrun]

If the sump runs dry your pump will overheat and possibly start a fire, at the very least you will have to replace your pump and possibly all of your livestock.
You should never restrict a drain line.
If your pump is too big you can restrict your return, but not your drain.

+1 on the pump burning up, but I would argue it's okay to restrict the primary drain provided you have a full size emergency drain without a valve to back it up.

 

[Heelfiend]

Okay let's back up and punt then.

With my 1.5" and 1" bulkheads through the bottom of the tank a given, what's my ideal setup? I am not drilling any holes in the tank but I am not completely opposed to going over the back (I have a canopy that we custom built and can drill a hole in that) for the return. I could use one of the drains for the primary and one for secondary and go over the back for the return. With a 951 GPH pump which should be the primary drain?

 

[thegrun]

What size it the tank? I would make one (Depending upon the tank size) the primary drain and the second the emergency drain with over the top returns.

 

[Heelfiend]

The tank is 120g, 4' x 2' x 2'.

The 30g sump has 3 chambers, small ones on either end and a big one in the middle for the skimmer.

 

[thegrun]

If you limit the flow through your sump to 600 gph then make your 1" drain the primary with a gate valve for adjustment and the 1-1/2" drain the emergency. If you go over 700 gph after head pressure loss through the sump the 1-1/2" would need to become the primary.

 

[thegrun]

Is one of the smaller sections the return pump section?

 

[Heelfiend]

Is one of the smaller sections the return pump section?

Yes. Mainly because the Reef Octopus skimmer I have is way too large for the smaller sections. I bought the sump from glasscages and I am confused as to how it's supposed to be used, really. The two smaller sections are on the sides and the left smaller section has glass partitions on the bottom of the tank in addition to the ones that go the full depth of the tank (under-over). On top of those partitions there was a piece of that light grating that people use on the bottom of their tanks to prevent rock movement.

 

[Heelfiend]

 

[pbaldwin]

If your willing to utilize both holes for a drain system and do the returns over the back read through this thread.

http://www.reefcentral.com/forums/showthread.php?t=344892

It outlines and clarifies the idea of a two drain system utilizing one as a syphon and the other as a backup.

The idea is further refined and made safer in this thread

http://reefcentral.com/forums/showthread.php?t=1310585

Both can be a bit of reading but are very helpful. The idea being use one of your drains as a syphon, as that is completely silent, and utilize either one or two other drain lines to handle the small amount of drainage required and to act as an emergency if the syphon becomes constricted.

The less water that an open channel drain handles the quieter that you can make it so if you can get the majority of your flow through the syphon line you can get your system near silent.

 

[Heelfiend]

Thanks for the links! Given a 951gph return pump, which do you think should be the primary/siphon drain? Will putting a ball valve on the return pump side make a lot of noise?

 

[julie180]

Any time your restrict water, there is a chance for noise.

Maybe some one already said this, maybe not. Your tank can not drain out any faster than its filling up (unless you have a leak somewhere). You only have to be concerned with it filling faster than it can drain.