Standpipe change

[frdagaa]

I have a AGA 90g bottom drilled with the Megaflow overflow, but it's loud and the standpipe doesn't seem to be the newer quieter version. Forgive me my stupidity, but I don't totally understand the plumbing (I didn't put anything together on the tank myself, which doesn't help) and am a newb.

So if I want to change out the standpipe, do I have to drain the whole tank?

Maybe I can just siphon out the inner overflow box? Or other solution?

Also, when I turn off the pump the sump fills up just a bit as expected; no where close to overflow. But when I disconnect the return line and overflow drain into the sump, there is very slow dripping from both lines that never ceases (over a couple of hours, so not just condensation/etc). This makes me worry that if the pump stopped while I was on vacation, I might have a disaster on my hand. Any suggestions about when the drips are coming from and what if anything I need to do about it?

BTW, nothing alive in the tank yet, just sand, so if I'm going to need to fix something, would rather do it now!

Might come next Tues to meet folks. Seems like a great community.

 

[kilo32]

When you turn off your return pump the tank continues to drain until it goes down to the top teeth of the overflow. This is the increase you see in the sump. If you want to change your standpipe you should be able to just pull the standpipe out from inside the overflow chamber and the water that is in the chanber will also flow into the sump. There should be enough room in your sump to handle the increase load of water as long as your sump was sized for your tank and wasn't too small. The bulk head fitting that both your drain and retun pipes push into from the overflow chamber will remain in place. Then it's just a matter of pushing into place a new standpipe and starting the system back up. As far as the dripping I'm not sure if I understand where you've discontected the return but if the return is still attached to the bottom of the tank at the overflow chamber then the mechanism that should be in place to stop water from siphoning back from the tank to the lower sump is a "check valve" that allows water to travel from the return pump to the tank but doesn't allow water to travel the other way. A failure of a check valve would allow water from the tank to siphon back towards the sump until the water in the tank lowers down to where your retuurn line(s) are located inside the display tank whenever the pump is off. If you are seeing a dripping then you may need to change that check valve as it may be failing slightly or just add a second one between the return pump and the tank. While you're working on that return line you can just pull the return pipe from the overflow chamber just as you did with the drain pipe.

 

[grimreefer]

Is the water dripping from inside the bulk heads? If so, this is because the stand pipes are only dry fitting in the bulk heads in the overflow box and not glued so you can remove them easily. This will cause a slight drip. If the overflow box is sealed properly then what is in the overflow box is all that will drip out. When going on vacation, it is good to have someone check on your tank daily to catch anything that might go wrong.

 

[frdagaa]

Thanks, folks. I think I got the standpipe thing taken care of. Still not sure about the dripping, but I don't have any check valves in the system, and think putting them in is a good idea.

 

[frantz]

While I know you already got it done, adding a valve below the standpipe (aka under the tank) is a good idea for general control of the return, and you could shut the return totally off to change the pipe without worrying about the extra water in the sump. More useful for the control aspect but it came to mind. Check valves are huge, there is alot of water to be sucked back into the sump in the event of a power failure.