clear layer on top of refugium water

it flows from overflow box back to sump.

 

you could point a power head at surface and see if that will stur it up.

 

I was tryin to see if it were a dead bacteria film from lack of surface aggitation (which is VERY commmon) or if it were some living organism or mold.

Both of what the others said are good ideas. But you will skim the top by initally draining like that over-flow should. Introducing that dead bacteria back into the water doesn't eliminate it. You need it to be skimmed off the top (like that over-flow should be doing) and into your sump area to be mechanically filtered or aerated and disolved by protein skimmer.

 

the water just needs to move. Kind of wierd to put a pump in a refugium just to circulate water. I guess it is kind of a wierd set up!

 

Your mangrove set-up is dead on my Frag set-up.. dead on. I drilled a 1" hole in the bottom of the tank for a bulkhead and put a 1" pipe a little over an inch from the top. My pump pumps the water in with a ball valved flow so it isn't radically out of control and the water has nowhere else to go but to that hole in the 1" pipe.
God, I wish I had my camera! I could show you.
DEAD ON!

 

Why is over flow not drawing off top of tank. If I lower box it will just lower water level and I will be right back where it is now.?

 

That is why I was saying don't get jumpy tryin to fix it just yet.
lowering the box only accomidates more water flow from a higher gph pump. If you're pouring water in, you'll want to lower it so it doesn't over flow out of the tank. If your pump it slower, you raise it so you cant see the air gap at the top of the glass.

Did you try to get that air bubble out?

Your next step would be trying to get more water flow in the tank (at the other end) but baffled so it isn't too ruff for sea horses. Then, with that bubble out, get a good flow through that U-tube.

 

My apologies, I didn't clearify. You can leave the inlet there and increase your flow rate but you could also take a piece of pvc and drill holes in it (facing the unattractive holes toward the back of the tank but on a downward angle) in attempts to deflect any direct water flow that may "unhinge" a sea horse... follow me?

 

If those holes dont take away from your viewing pleasure, you can use them for extra surface aggitation but you wont need to once you get that over-flow sucking right.

 

I think I get it that would remove the over flow box and any chance of losing siphon and flooding. Happened once and lucky enough to catch it within 5 min.