A couple updated shots as the grass reaches its zenith in terms of coverage:
I've been battling some algae issues on the grasses themselves, since the hydroids that grow on them tend to trap detritus. Adding an extra powerhead here recently really helped.
Seems like since the grasses have reached their outward limits, they're starting to go up. The leaves are a lot longer than they were earlier (it looks like).
Can we predict some peppermint shrimp in your future?
It's probably going to have to be more drastic than that, actually. There are probably 1000 of them in there. The lack of filtration encourages a lot of copeopods and other planktonic stuff, which the Aiptasia really seem to like. I'm sure the 250w of halide baking them daily isn't helping, either.
3 worked perfectly in a heavily infested 90 for me. Took about 2-3 weeks but they got every one. Now I'm done to just one shrimp and I haven't seen even a tiny aiptasia in 10+ months.
Large sized specimens seem to work much better than tiny ones.
I'd give peppermint shrimp a try also. The tank at my wifes work was covered in aiptasia and from what she says it is now clear. We put in about 4 or 5 small peppermint shrimp that didn't last long with a clown fairy wrasse and didn't seem to put a dent in the aiptasia. We then ordered 6 more in a reefstogo order and they were monster sized peppermint shrimp. They survived the wrasse and I'm told she can't find an aiptasia in the tank. It had probably a hundred or so in a 65 gal tank. I'd give 1 or 2 larges ones a shot.