Sump Refugium Combo - will this work?

When I got my new drilled tank I purchased a Mega Flow 1 undertank sump pictured below. It has a separate chamber for the drain pipe which has various slits cut in it so the water can fill up the chamber and then empties via an overflow opening at the top of the chamber. That flows through the black box with filter floss in it trickling through holes in the black box through bio balls (which I immediately removed). The water then accumates in the area below and flows over a short baffle through a sponge then under a tall baffle to the chamber that holds the pump. The sump area that holds water really doesn't have room for much more than the heater, so I decided to try and make it a refugium. I put in a 2 inch sand bed and on top of that put small live rock pieces and a chunk of chaeto. I hung a 5000K "daylight" pc spotllight purchased at Home Depot to light the sump. I also put a small fan over the sump to cool it if the light makes it too hot. I just added the refugium stuff yesterday so today is the test for heat build up. The sump pump is rated at 700 gph but I had to dial it down via a ball valve I installed, so I'm really not sure how much flow the sump gets. I've added some shots of the finished product. Will this work for added natural filtration and/or a place to raise pods? What am I not doing right or need to change/improve?

THANKS!
Denise

 

My tank is a 55 gal, pictured below - forgot to mention that!

 

Here are sump pictures:







Thanks in advance for any feedback. As you can see when I took out the bioballs I just put in an extra square of floss.

Denise

 

From what I see looks good but I didn't see a skimmer,that would help on the filtration and be sure and keep the sponges clean or it will build up with waste and what not and raise your nitrate levels. Have you unplugged the pump to make sure it doesn't overflow if the power goes off? Looks alot neater than my sump/fuge...lol.

 

I've been using this as a sump for a while, so yes I unplugged the pump to be sure there would be no overflow issues. All's well there. Since I can't fit an in-sump protein skimmer I was actually considering using a hang on skimmer I used with a different tank. I am considering hanging it on the sump itself but I would have to adapt the length of the tube that draws the water into the skimmer as it's not long enough to reach the water. I may play around with that thought for a while. I would really like to keep things out of the display tank if I can.

Anyone else hung a skimmer on their sump?

Denise