Constantly Adjusting Drain Valve

cjpitt80 · Mar 3, 2020

Hi,
I'm running a 16" Shadow Overflow setup as a Bean Animal. Tank has been up running for almost 2yrs. Over past month, I have to keep adjusting the main drain valve. I get it quiet with just a tiny trickle coming out the full siphon pipe, and it works fine. 8hrs later, main drain is sucking in air, dumping bubbles in the sump, and loud so I have to close the gate valve a little more. 8hrs later, repeat. If I shut off the return pump (Reef Octopus Varios 6), when I turn it back on, the full siphon drain is sucking in air and I have to OPEN the gate valve on the main drain to quiet it down. 8hrs later have to close main drain again because now it's sucking in air. It's almost like my return pump slows down after a few hours of continuous use?? I vinegar cleaned it, and same thing happens. Every 8-48hrs I'm slowly closing down the main drain. Anyone have any ideas what's going on? Is my return pump dying?

Reef AquaCult · Mar 3, 2020

What is height difference between primary full siphon and secondary drains? Do you have a strainer on full siphon and is it clogged? It might be a problem in the overflow box and not the pump. Do you have any strong powerheads that turn on and off inside the tank because flow inside the tank can cause changes in the overflow water volume as well.

ca1ore · Mar 3, 2020

Not sure i really follow …. maybe it's terminology. Main siphon drain/primary valve should be adjusted so that a small amount of water goes down the secondary. Emergency always stay dry except when there is, well, an emergency. If your main siphon/primary starts sucking air, then something has reduced the return flow. It may be that the pump is failing, or has developed greater flow variability. My main pump can vary by about 50 gph over time, which messes with the drains. I just run a bit more than a trickle through the secondary. Has anything lese changed with your system. Changing water levels in the return section of the sump will affect net return flow by small amounts.

cjpitt80 · Mar 3, 2020

Have the pipes at the recommended height by synergy reef. I think it's 7" emergency, 5" full and 2" main maybe? Can't quite remember, but I haven't changed them. Box comes with 2 weir strainers and I switch just switched it out for the clean one. I don't have any strainers on any of the pipes, just the U-flow elbows that come with it. I opened the box and cleaned sucked everything out, but there wasn't really much in there, just a few limpets and calcium deposits. I can see down all 3 pipes and there's no significant obstructions.

PS for reference is the MAIN drain the one with the gate valve, correct? OPEN drain is the full siphon one, correct? Just want to get terminology right for newbies. I thought I was FINALLY out of the newbie phase, and I can't remember the early on stuff lol

Reef AquaCult · Mar 3, 2020

What about pumps turning on and off? You want to have a good height difference between full siphon (gate valve) and secondary (trickle) which gives you a cushion for siphon to develop and small flow changes.

Rybren · Mar 3, 2020

The main drain with the gate valve is the siphon. It should take the bulk of the flow.
The open drain is the secondary. There should be just a trickle running through it EXCEPT when the siphon is blocked. Then the water will rise in the overflow box, cover the hose on the secondary, and convert the secondary into a siphon.
The Emergency is just that - for emergencies when major blockages occur on the other lines. Should normally be dry but it usually will take some flow on startup.

cjpitt80 · Mar 3, 2020

ca1ore said:
Not sure i really follow …. maybe it's terminology. Main siphon drain/primary valve should be adjusted so that a small amount of water goes down the secondary. Emergency always stay dry except when there is, well, an emergency. If your main siphon/primary starts sucking air, then something has reduced the return flow. It may be that the pump is failing, or has developed greater flow variability. My main pump can vary by about 50 gph over time, which messes with the drains. I just run a bit more than a trickle through the secondary. Has anything lese changed with your system. Changing water levels in the return section of the sump will affect net return flow by small amounts.

Yeah I think my terminology may be off, but that is how I have it set up. Thing is nothing has changed in the tank. The ato dumps into the return section and changes the level maybe 1/4" at a time, but that didn't cause a problem the last 18 months. My return section is after my chaeto in the sump and can get gunk on it, so maybe that lowers the return rate a little and causes issues? But again, this has really only been a problem the last month. Just seems like every other day or 8hrs I have to close down the main drain a little more. Weird thing is when I turn pump off to feed. When I turn BACK on, the valve has to be opened back up to quiet down the 2ndary drain..

cjpitt80 · Mar 3, 2020

Rybren said:
The main drain with the gate valve is the siphon. It should take the bulk of the flow.
The open drain is the secondary. There should be just a trickle running through it EXCEPT when the siphon is blocked. Then the water will rise in the overflow box, cover the hose on the secondary, and convert the secondary into a siphon.
The Emergency is just that - for emergencies when major blockages occur on the other lines. Should normally be dry but it usually will take some flow on startup.

OK got it. Yeah, that's how I have it set up

cjpitt80 · Mar 3, 2020

Reef AquaCult said:
What about pumps turning on and off? You want to have a good height difference between full siphon (gate valve) and secondary (trickle) which gives you a cushion for siphon to develop and small flow changes.

Yeah that's another thing. BEFORE, when return pump was off then turned back on, I wouldn't have to make any changes, the flow would go down the emergency drain for maybe 10sec, then everything would even out. NOW it seems like I always have to open up the gate valve once the pump is back on and emergency flow stops to quiet down the 2ndary drain after a pump power cycle. Thing is NOTHING has changed. I hadn't even opened the back of the box in probably 10 months. I've NEVER changed the pipe heights. Not sure what the heck is going. It's annoying and I'm constantly slowing down flow thru the sump to keep the tank quiet

Pntbll687 · Mar 3, 2020

Do you have vermetid snails in your system? They can cause blockage in the pipe which could cause an issue like you describe.

Can you easily take apart the plumbing? I would take it apart if possible and check for blockages.

What type of return pump is it? If it's a DC controllable pump you could try adjusting the return pump instead of the gate valve.

K7BMG · Mar 3, 2020

As you have stated you have cleaned out the return lines and they are clear and unobstructed. So that being the case the drains will do there thing same as always.

The only thing that could be an issue is the drain Gate valve may be failing and allowing the gate to move. Rare but I have seen this in the past.

You say you have cleaned the return pump.
But have you checked and cleaned the return pump LINE.
You may find that something has gotten in the return line and messing with the flow.
Or as you suspect the pump is failing.

IMO the drain lines are not your issue here, its something else.

cjpitt80 · Mar 3, 2020

Pntbll687 said:
Do you have vermetid snails in your system? They can cause blockage in the pipe which could cause an issue like you describe.

Can you easily take apart the plumbing? I would take it apart if possible and check for blockages.

What type of return pump is it? If it's a DC controllable pump you could try adjusting the return pump instead of the gate valve.

I do indeed have vermitid snails either/or/and those little limpet things. I can't "easily" take apart the drain lines but when I pulled the U flow elbows off the pipes I could shine a light down and there certainly weren't any big obstructions. Nothing that would slow it down over a few hour period I would think. Pump is a DC Varios 6 That runs on full level all the time. I haven't adjusted it, but I guess I can try that

sarcophytonIndy · Mar 3, 2020

cjpitt80 said:
Hi,
I'm running a 16" Shadow Overflow setup as a Bean Animal. Tank has been up running for almost 2yrs. Over past month, I have to keep adjusting the main drain valve. I get it quiet with just a tiny trickle coming out the full siphon pipe, and it works fine. 8hrs later, main drain is sucking in air, dumping bubbles in the sump, and loud so I have to close the gate valve a little more. 8hrs later, repeat. If I shut off the return pump (Reef Octopus Varios 6), when I turn it back on, the full siphon drain is sucking in air and I have to OPEN the gate valve on the main drain to quiet it down. 8hrs later have to close main drain again because now it's sucking in air. It's almost like my return pump slows down after a few hours of continuous use?? I vinegar cleaned it, and same thing happens. Every 8-48hrs I'm slowly closing down the main drain. Anyone have any ideas what's going on? Is my return pump dying?

Apart from something periodically clogging your main (gated) siphon pipe, I would say it may be an issue with your return pump or its controller. Is it a DC pump? If so, what percent/wattage is it set for?

GlassMunky · Mar 3, 2020

Sounds to me like your pump isn’t holding a steady flow and the pump speed is changing...

cjpitt80 · Mar 3, 2020

K7BMG said:
As you have stated you have cleaned out the return lines and they are clear and unobstructed. So that being the case the drains will do there thing same as always.

The only thing that could be an issue is the drain Gate valve may be failing and allowing the gate to move. Rare but I have seen this in the past.

You say you have cleaned the return pump.
But have you checked and cleaned the return pump LINE.
You may find that something has gotten in the return line and messing with the flow.
Or as you suspect the pump is failing.

IMO the drain lines are not your issue here, its something else.

Hmm... Gate valve seems fine, the Phillips screw is tight, but I guess I can try to see if it moves somehow. I actually have never TOUCHED the return line since I set it up. I guess I'll check that. I'll check everything before I get a new pump. Sadly the more I think about it, the more I think it's the pump. I can't think of any reason that the flow rate would change over a few hours to days other than the pump. All those obstructions etc seems like once adjusted for, would be constant. In my mind, only variable would be the actual valve, or the pump.

cjpitt80 · Mar 3, 2020

GlassMunky said:
Sounds to me like your pump isn’t holding a steady flow and the pump speed is changing...

Yeah. More I think about it, the more likely that seems. Turn on it's at 10. 8hrs later it's at 8. a day later it's 6. Turn pump off, then back on and It's back to 10...

(numbers mean NOTHING just illustrating the basic situation that's going on)

K7BMG · Mar 3, 2020

cjpitt80 said:
Hmm... Gate valve seems fine, the Phillips screw is tight, but I guess I can try to see if it moves somehow. I actually have never TOUCHED the return line since I set it up. I guess I'll check that. I'll check everything before I get a new pump. Sadly the more I think about it, the more I think it's the pump. I can't think of any reason that the flow rate would change over a few hours to days other than the pump. All those obstructions etc seems like once adjusted for, would be constant. In my mind, only variable would be the actual valve, or the pump.

It depends on the obstruction and how it moves in the line.
But I still think your issue will be found on the pump and return line over the drain.