DT overflowed

It's a standard 90 gallon drilled, with a corner overflow (see picture at bottom of post)

The PVC leading to my sump is about two inches wide, and two feet high.

I checked earlier and I saw a snail going into the pipe, but the snail's size in proportion to the PVC's is pretty negligible.

I don't think my return pump has the option of switching how many gph it does.

The tank has been up for approximately three months.


The water level seems to be stable at the moment, but I'm still worried that the problem will occur again. All I did to fix it was add a smaller hole beside the one already on the PVC cap, instead of one bigger hole (I did this in case the hole would be too big.. You can cover a hole, you can't really cover half a hole).


I appreciate the replies

EDIT: Here's the picture. I couldn't really take one of mine, since it's lights out for my tank

 

Sounds like it worked to me. The advise that I was given and want to pass on is that several smaller holes is better.
I actually have 4 holes in each of my stockmans. One of them has a valve on it that is completely closed as it allowed too much air and wasn't flowing correctly. Here is a pic of what mine looks like.


Also anything going into the overflow can cause issues. Even if it is not that big it will inhibit the flow and cause issues. Did the snail go all the way in?
If it did I would see about getting him out.

Most return pumps don't have an option to control the flow. The best thing to do is add a ball or gate valve on the return side of the pump to dial it back if necessary.

 

There is nothing in your setup that would cause anything out of the ordinary. That leaves only two possible culprits:

- The apparatus you're using at the top of the drain (which looks like a Durso). Likely the hole size - not much else can go wrong there.

- Something is in the drain pipe somewhere along the way (like a large snail) that's restricting flow.

More stuff:

- If you don't have a strainer on the durso you should put one on. A turbo snail going down a drain can cause a lot of problems. There are strainers that fit inside most standard PVC fittings so all you'd need to do is just put it in. Easy.

- On the pump thing, you can lower flow by putting a ball valve on the output.

 

I'm thinking that air in the line might cause less head pressure, causing the flow rate to increase until the air is gone

 

The durso does have a strainer on it, and yeah, there was a large snail in the PVC but I took it out. The water level in my sump seems to be regulated, but the water level in my DT is still a little high

 

Rocketman has pretty much covered it. In any durso/stockman type set up, it is important to not allow a siphon. A siphon flows much more water that a pipe filled with air and water. Sorry to point out the obvious. But the point is you need a air break to prevent a siphon.

If the air vent gets plugged, then the drain will start a siphon until it empties enough water out of the over flow to make the drain inlet the air vent... it allows air in, breaks the siphon, and the overflow fills up again. This surging is annoying, and depending on volumes and setup it could starve the return pump.

So the air part has been taken care of... the only other thing possibly is somehow the pump out put has changed. As was said, drains are temperamental and if something changes it could throw things off.

Have you cleaned the pump?
Do you have a filter sponge you cleaned?
Is there any way you can think of pump output increased or decreased?

If anything... take the pump apart and clean/inspect it. If this continues, you could put a valve on the output and slow flow a bit and see if it helps. It seems like you have gone as far as you can with the air side of it.

 

Something I found that works well with my Stockman and Maggie Mufflers is to insert a piece of air line down in the drilled hole in the standpipe cap and adjust it up or down until you achieve the balance between flow and noise. Once its set it is rock steady.

I also found too much air is worse than not enough air as far as noise and level jumping up and down. I have a couple standpipe caps and the ones with multiple or larger holes are worse than the ones with a single smaller hole or even an airline valve inserted in the hole to regulate the air mixture.

 

I didn't clean the pump, but I cleaned the filter sponge to try to fix the problem. Nothing that I know of changed regarding flow or parts or anything, so maybe the problem WAS the snail entirely

 

I have the same problem again, only worse now. I came home to my return pump sucking water, so I turned the valve so that no water was going to my refugium. I then took water from my fuge and put it in the other side of my sump so it would suck water again. Next thing I know, the DT is overflowing with water. I thought that removing the PVC cap would allow enough air for it to stop overflowing, but it didn't, so I ended up turning off my whole system. I'm assuming a snail had gotten in the PVC and restricted water flow into the sump.

 

It looks to me like all you have to do is push the durso down a little farther.Its shouldn't be sticking up so high.Mine is about 4 inches below the top of the overflow grate.It is adjustable so you can fine tune the water level in your sump and DT.Just make sure it is not too low to cause your sump to overflow.lol
P.S. It probably worked at first before the slime started to build up.