125 aggressive reef, leaking, need input....

[aquaknight]

My 125 is leaking, a rather large wet spot on the carpet in front of the tank has formed and not gone away in the last couple of days to spite trying to dry it. I had noticed water usage had gone up considerable.
Specs on the tank are:
125gal non-drill Oceanic 125
Aqua C EV-240 Skimmer w/Mag 18 pump
1200gph CFL Aquatics Overflow
Mag18 return pump
Wake2k Center 4000gph model
Aquanetics UV light
Little Fishies phosban reactor (running lots of carbon ATM)
29 refugium
And a picture of the sump. It looks more complicated then it really is:

Two days ago I turned off the refugium and phosban reactor/UV light. There's one pump for the fuge feed, and one pump for the reactor/UV. Water level in the fuge has remained consist. Yesterday, I turned off the return pump and pulled the overflow tube. Water level in the sump has stayed the same and water level in the tank has stayed the same as well. (I marked all the levels wth a piece of tape). I have kept the skimmer running as it's external to the sump.
The only things I can think of now, is that I should turn the reactor/UV back on and see if that drops the sump's level. If that doesn't, it almost has to be the intake/return piping? They all have fair amounts of salt creep on them. More then I would typically expect, but not enough to make that bit of carpet that wet?
I guess I will pull the pipes then I get home and fill them with water to see if they leak. They all have ball valves on the end, so I was just going to close them, and stand them up and fill. Or with them just sitting filled with water not be enough? I'd have to have them under running conditions to possibly leak (esp. the return?)? I also guess it would be a bad idea to just drain the sump and pull it to inspect. I consistently hear saltwater use will fatigue the plastic and make it brittle then crack. I would think if it were to turn brittle enough to crack, it would be some type of considerable crack, something catrosphic and I'd be losing a whole bunch more water?

 

[osuaquarist]

How are your pipes connected? we had a lot of trouble with leaks until we used plumbers tape to seal our connections, also try and get them as tight as possible, maybe use some big pliers to turn when you can't by hand.

 

[aquaknight]

All of the intake/return lines are slip PVC, except some Loc-Line I used on the top of the return line, but that hangs over the tank. I used PVC cement on 90% of the lines, I think I didn't cement on the union that connects to the overflow. Though none of the lines really have 'wet spots' just a lot of salt creep. I think I might put new pipes in as you can kinda see right below the UV light, I split one of the intakes because I wanted to feed the refugium with it, but the 29gal is too tall for 1" PVC to fit.

 

[aquaknight]

Here's a bit of an update. Pulled everything out minus the refugium. Water tested the piped and look what I found:

That is only after about 15mins. A slow drip, about 1 every 4-6 seconds.
Here's where the rubbermaid sat, took a look, pretty much half way inbetween the knots, you can see it's wet:

The bottom area pretty much exactly where that pipe sat just above the sump. The rubbermaid is still not out of the clear yet, as it had salt creep stemming from some of the 'ribs' (vertical plastic supports, at the ends, a couple of the ends and one corner had salt creep. It's filled and waiting to see if the water level drops at all.
I do have a question though, while my 125 remains sump-less, will it be okay for another day or 2? My Wave2k had remained on, and I added a Maxi-Jet 900 for some more surface agitation. I've also cut back on heavy feeds too. Any other suggestions welcome!