Rebuilding hardware set up

[xtreme]

What type of overflow do you have? On a properly designed system, the water level in your display tank should only drop an inch or two max when you have a power outage. As mentioned your sump needs to be able to handle this to prevent flooding. Your sump should be fine for your size tank. A fluval filter losing power shouldn't really effect your water level as it is self contained.

[pterfloth]

The return line I mean is the return line from your sump via your return pump from the sump to your tank. Water can drain from your tank into your sump during a power outage in two ways: through the overflow until the water level in the tank drops below the top of the overflow and secondly, it can siphon via the return line from your sump return pump back into the sump. One should set your maximum sump water level so that when both the overflow and the return pump drain to the sump there is enough room to handle it. The overflow may not be the problem but return line back to your tank may be submerged too low. You can fix this my raising the return line and not submerging it so much. You should check this and adjust it in any case.

What I suggested was that shut off your return pump, immediately raise the return line out of the tank and then allow the tank to drain via the overflow until the overflow stops. If this is already enough to overfill your sump then you need to lower the level of water in your sump.

I know the scary feeling you get when the sump starts to fill. This is a solvable problem.

Hope this helps. Feel free to ask for more specific advise.

[jassz]

The item at the back of this picture is attached to the line coming out of the sump pump. So that is how the water is returning to the tank, correct? If I disconnect power, does water flow back the other way?

The item at the front of this picture (the U shaped thing) goes back to the Fluval filter. Is this what you mean needs to be adjusted higher so less water drains back?

I can't see how it can be the first item (at the back of the tank) as it is submerged into the tank several feet.

[pterfloth]

Hi. Well if the line at the back is connected to the sump pump and the water returns to the tank through this line and it runs down to the bottom of your tank then you have got a problem. The return pump fills this line with water. When the power goes off, the water is going to siphon back through this line into your sump and will continue to do so until the level in your tank is low enough for this line to lose suction. By that time you going to have a big puddle somewhere you don't want it and your fish will not be happy. Most people's return line outlet ends just below the normal water surface to prevent siphoning out their tank. I'd shorten the line a lot so that you don't have this happen. You may also be able to find a check valve to put in the return line, but I don't know of any. One of these days the power will go out.

[jassz]

Do you think the lines are probably reversed? To me, the line at the back looks like the water-out lines on my FW tank. It has a cover over the end so the fish don't get sucked up in to it. The line at the front looks like it should be adjustable for height, hence, maybe it is supposed to be the line in to the tank, and the siphon out line when the power is off.

But the line at the back is definitely the line in at the moment, because if I pour water into the sump, or if it gets air in it for a second, it's definitely coming out the back line.

[pterfloth]

That could be the solution. The lines in and out of the Fluval don't matter since it is enclosed. Connect the front tube to your return. It actually looks upside down. On mine, the "U" sits over the tank lip with the flared end just below the water surface.

I suggest turning off your return pump and quickly disconnecting the return hose from long line at the back. Loosen any hose clamps first so you can do it quickly. Once the line is disconnected your chance of massive draining should eliminated. Turn off the Fluval and swap the lines. Try inverting the "U" so it sits over the tank lip.

I think this should work. The overflow will still drain some so you do need some room in your sump for that.

Let me know how it goes. Good luck!

[jassz]

Well, mostly.

I figured out the plumbing (and it wasn't the way I thought). I am satisfied now I could survive a power outage with dry feet. More importantly, I'm not so intimidated by it any more.

I got the wiring tacked up nicely. I changed out 10% of the water and vaccumed the gravol. I moved the live rocks from the sump in to the tank (tried to create interesting caves etc for the gang... they seem to like it), and most importantly, I got the protein skimmer installed! It seems to work great, but it is frothing out the top which I figure it shouldn't do. I tried adjusting the water level with the pipe at the side, as I was instructed, but it's still frothing. I think I might have too much water in the sump, but taking some water out won't work as the skimmer isn't in the lowest point. I have to change the partition wall, I think. But does it matter if it foams out the top?

I didn't get the second heater installed, but we'd all had enough for one day.

Thanks everyone for your help!

[jassz]

Originally Posted by xtreme

What type of overflow do you have?

I don't know how to answer that, except to post a picture...

Amazingly, I just found a webpage with my overflow, it even has that exact aqualifter, though I had no idea why that was there (it's not sitting near the overflow box, but rather underneath).

http://www.drsfostersmith.com/produc...fm?pcatid=3642