To Improve My Existing Setup...

I've attached some photos of my current setup. If you wouldn't mind, please have a look and tell me what you think based on what you SEE. Give it to me straight... I can take it!

#4570 is a head-on view of the tank. It is my understanding that all of the coralline algae is a sign of good water quality. Is this true? Also notice on the sand bed on the left side... there is some brown algae growth

#5242 is a hang on Aquaclear filter. I have it there just for water circulation and a place to keep my protein skimmer.

#6434 is a shot of the right side of the tank.

#6452 is a closeup of the hang on filter... you can see the protein skimmer in the back.

#6742 is a shot of the left side of the tank. I have a power head the the bottom pointed back behind the live rock to keep water flowing through the rock. Also, I have a 4 stage canister filter which contains from top to bottom:
Tray 1: Small bits of live rock and filter media.
Tray 2: Ammonia scrubber pad and filter media.
Tray 3: Nitrate scrubber pad and filter media.
Tray 4: Chemipure pouch and Activated Carbon.

If you were charged with making this tank thrive, what would you do?

Why are you running the ammonia and nitrate scrubbers?
Is the algae diatoms or slime?
What are you running for lights?

I would lose the canister filter. They tend to cause more nitrate problems than anything else.

+1 @Aquarian

I like the set up. How many gph is moving in there right now?

Display = 20 gal

Total = 26