IME, with euphyllia like torches and frogspawn, less flow is better than more flow. I have a big group of them (5 torches, 1 frogspawn, 2 hammer) in my 40 LPS tank, and they open up best under lower flow. the flow is fine; so long as the water is moving, the surface is agitated, and you're cyano-free, there's really no need to increase flow in any tank. unless you're noticing dead spot or keep SPS.
the filter could be used to hold carbon and/or some filterfloss to catch detritus; if you want to convert it to a 'fuge, all you'll need is a small light of some sort, and some cheato to put inside.
if you have algae, your cleanup crew should take care of it. all new tanks go through an algae stage where they look like crap, I've been through more than my fare share, and have found the only thing you can really do is just wait it out.