Scooter blenny in 10g, can't keep tank clean

[dendro982]

Have a problem: by mistake, I bought 2 male scooter blennies for 90g tank. The weaker one was constantly under attack, and after one of his eyes was badly damaged, I removed him to another tank, now it's 10g. Recovered fast, in 3 weeks.
Because scooter is of dragonet family, it should be fed frequently - in my case tank receives 2 times daily 1/4 of the mysis or Marine Diet cube. Water fouls quickly, no ammonia or nitrites, but film and red smile algae, water eventually looks viscous, some gas bubbles on LR. Nitrates are around 20 ppm, no phosphates.

Power filter is not picking all the particles, a lot sets on the bottom.
AquaClear 50 power filter with carbon, Purigen, frequently changed floss and frequently washed sponge to keep floss in place.

Increased flow - added Mini-Jet 606, still - all is floats for a some time, but not filtered, accumulates eventually under the rock.

Without scooter similar tank did much better. I can't get rid of one-eyed fish, placing him back in 90g will lead to the attacks and painful death, euthanize?
Other way - I can add sump and skimmer, all I have at the hand is a bit oversized - ASM Mini-G. No space to hide sump, and this is a sleeping place, and skimmers are noisy.

Tried more frequent vacuuming - can't reach under rockwork this is after cleaning:

What are better husbandry practices and what should I do to keep tank in a better shape, in a least noisy and obtrusive way?

P.S. I have an empty 20g L tank, Eheim Liberty 200 PF, micron socks, but no more LR.

 

[ratimpulse]

Well if you can I would suggest working the 20g L into a sump and running more flow to the tank. I would suggest 2 PH, 1 in each corner pointing towards the middle on the bottom. Do you do water changes, protein skimmer?, and whats your cleanup crew consist of?

 

[BLKTANG]

U need hermit crabs.

 

[flfirefighter13]

Hermit crabs and more flow, keep the detritous stired up untill it gets picked up by the aquaclear, may try a wavemaker or timer of sorts to randomize the fow

 

[dendro982]

Thanks for the suggestions!

Clean-up crew is mainly a several spiny astrea snails, moved hermits to the big tank, because they like to mess with corals, causing them close. And they killed all, but one, astreas in previous setup. Also there are 2 mintrax crabs for the valonia.
I tried snails this time to clean LR.

Now there are 2 main sources for a water movement, both on the back wall: Mini-Jet 606 (~150 gph) and AC 50 power filter. Flow reflects from the front wall, goes under LR to the back. A lot of debris is collected under LR - could be rock shedding too.

What I don't understand - power filter is not capable to collect and filter debris in the water column. After basting LR all flows in the water column, and settles back on the bottom.

Now I'm keeping water quality by frequent 25% water changes.

I have also slightly oversized skimmer, not in use - ASM Mini-G. Seriously considering adding this skimmer and a sump for it. Started to assemble, but the Maxi-Jet 1200, that I planned to use as a return (side-by-side sump, no head loss), is too loud for a sleeping place. Quiet Mini-Jet 606 moves only 150 gph - for filtration and skimming. Will be not enough?

Just in case, ordered today OceanRunner 600 gph pump - to run it few times a day, raise and remove debris. Daytime only, as the skimming. Sale, you know. If the idea is reasonable - I'll use it.

Will it work, what do you think? Or it will smash fish?
I'm trying to do what ldrhawke did in his barrel-shaped tank.

If it will work, will the 1/2" spray bar under the rim be enough, or I will need 2 powerheads anyway, for a bottom flow?