From my understanding, you can roughly use a per-gallon rule for your cleaners, so you could go with 1/3 of the numbers, plus a snail or two.
Search the forums for "hair algae" as that's what the grass-like stuff is. I know a lettuce nudibranch will eat it, but once the hair algae is gone, it is the ONLY thing the nudibranch eats, so it will starve unless you feed it.
135W should be ok for just a 45g FOWLR
. Hopefully this helps you some.
125 gallon saltwater: 55gal sump, 4 Blue-Green Chromis, Purple Tang, True Perc, Firefish, Royal Gramma, 5 Ricordea, Bubble Coral, 15 Pulsing Xenia, Green Star Polyps, Deresa clam, Green-Tip Torch Coral (about 11 "heads"!), Orange Montipora Cap, Purple M. Digitata, Green Slimer Acro. Yongei, 3 Orange M. Digitata, Pink&Green Acro. Millepora