I need some advice/help!

I've a 5yr old 110g salt tank with a 30g sump w/refugium (UV sterilizer, Octopus skimmer, 2 bags chemipure elite in baffle as well as a bag of de-nitrator). Corals: 2 brain corals (red brain approx 8.5" diam & getting huge, other 4") multiple diff types zoas, duncan heads, trumpet, mushrooms, green star polyp. Fish: Flame angel 3", foxface 4.5", 5 small/med green chromis, comb tooth blenny 4.5", golden rainbow wrasse 4.5", blue tang 3.5", desjardin tang 3", royal gramma 3.5". Other: 3.5" maxima clam, small assortment hermits/snails. Sand bed about 2.3-3.5".

Ok, here's the question. From my experience it seems difficult to target one thing as a cause for an effect, but it seems that after I took out a lot of Chaeto to sell to the LFS a month ago, my nitrates and now phosphates are out of whack. Nitrates hovering around 25+-ppm and phosphates creeping up causing red slime (recently removed phosban due to age and havent replaced it yet). Do you think I've too much stock? I need to remove fish or corals? Just wait and let Chaeto grow back? Need more filtration like adding a canister filter? I already intend to put Phosban back in reactor once it arrives. My trumpet and duncan heads have been suffering (withdrawn) which I attribute to the high nitrates. No other corals showing stress.

One other minor question... I think it's diatoms (brownish) or algae slowly accumulating on the sand. It's not really bad, but the bed obviously doesn't look as nice as it did when I had a sand sifter. The problem is I've been through 3 of them and they never get enough to eat. I cant justify getting another one knowing it's just going to waste away and die. Any suggestions?

 

Does the tank have a lid?

What about replacing the chaeto, adding some chempure, type of GFO maybe some purgen.

Seems like a fairly heavy bio-load for the size but that could just be me. To keep the tangs and fox happy you have to feed, and up the nitrates go.

Can you steer me to a picture of the tank?

TIA

 

no glass lids, just egg crate. There is a wooden canopy w/power compacts and halides. There's a fan to keep lights cool and I generally always leave the 3 lids/doors open to the canopy to help with cooling.

I'm glad you mentioned the feeding. I meant to include that in original post...I was feeding every day 2 cubes of diff types frozen food dosed with Selcon, garlic and Zoe. I just recently stopped that and feeding every other day as LFS amigo suggested to slow intro of phosphates of frozen food into system. But that doesn't help me w/the nitrates! I do try to feed the tangs Ocean Nutrition's seaweed sheets at least every other day. When I get home from work I'll take some shots of the tank.

 

Thaw and rinse the frozen before adding to the tank will help reduce phosphates and some nitrates. Feeding less will help lower nitrates. The addition of Phosban will help on both fronts.