I've had some hair algae and all around other algae problems lately, so I thought I would report my results using a few things.
To first get it short enough I tried emerald crabs. I had about five in the beginning. They did a decent job, but they more of focused on certain spots and stayed in that area for a while (week or so). Although they did cleanup the medium and short hair algae in localized areas fairly well and did eliminate the little bit of bubble algae I had along with an aitapsia I found but forgot to deal with, they just were not powerful enough for my tank in the long run and I was afraid to add more since they are crabs after all.
I still have the foxface, which I tried next, and it has done a very good job at keeping the stuff at a very short height throughout the tank. After about 1.5-2 months I knew that my snail crew was not big enough, so I tried some fuzzy chiton's to cleanup the rocks to let the coralline algae grow again.
I bought seven, all about 3/4" to 1 1/4" long. After about a week they finally got used to the tank and started to move around a lot more. About another week after that I didn't need to flip them back over as often as I did before.
Overall they do an extremely good job at cleaning the rocks (the glass is so so), but they move so slow that it takes forever for an area to be cleaned, but once it is clean, nothing grows there for a while. They removed everything: detritus, hair algae, diatoms as well as other nuisance algae down to the dead coralline algae they were all growing on top of. Here is an image of the work from just one fuzzy chiton. It is about an inch long and the rock is about 9.5" long diagonally. It took about 2.5 weeks to clean it, but the areas where it first cleaned (lower left section) are now being covered again with algae, although this time 50% of the grow back is coralline.
Only trying out a few, I decided that although they work fairly well, they move too slow though the tank to be truly effective as with some, the areas that were cleaned a few days prior (about 3" away from where the fuzzy chiton is currently at), algae was already coming back.
Some have died for no apparent reason from what I can find, others are moving at only a few inches a day, and some are moving at several feet per day now.
All in all it seems to vary from fuzzy chiton to fuzzy chiton as to what it will do and how long it will survive as there doesn't seem to be much of a pattern between size, location of feeding in tank (high or low, rock, glass or PVC) or diet (One feeds almost entirely on diatoms and does quite well, others feed on the mix of junk found on the rocks where in such case some have died, yet others 6" away eating the same stuff on the same surface do perfectly fine).
Next I tried Mexican Turbo snails. Because almost all of the rock in my tank is zip-tied or cemented together or both, knocking over rocks isn't really a concern for me.
So far I have five large ones (1.75-2") and two smaller ones (1"). They have been doing a really good job so far and move reasonably fast through the tank. I tried just one big one at first and within two days it had completely cleaned the two square foot side panel and was already on the back panel of the tank on the second night leaving nothing but most of the coralline algae behind.
The side panel. It looked just as green as the rock to the right of it before the trial turbo was put in.
So far now being about three weeks after having all seven they have have continued to do a pretty good job, although I have noticed that they have slowed down a bit since I got them, but they continue to clean nonetheless. I may need to get five more large ones, but I'm waiting for now to see how things go while I continue to find ways to lower the nutrient levels in the tank.
Here are a couple other images showing the work done by the turbos. The shell was only half cleaned and so you can see what it looked like beforehand on the top right of the shell.
The algae grows back, but it takes close to a month for it to come back and never really goes away with time, so I knew that my cleanup crew was too small for my tank (which I kind of already knew in the first place as I didn't increase it much when I upgraded from a 80 to 180gal-stupid me, but wasn't sure what the best route would be, sea hare or a 1000 tiny snails sort of thing).
And now some random pictures, the first two are of chloropasts inside chaeto aerea.