I got 10 medium snaila and 6 very large snails in my tank, along with about a dozen smaller ones. I have a 125 gal
tank and they do a pretty good job at cleaning the tank of "brown" algea.
I was also told from the good people here that my tank being new would go through this stage. Just to let nature take it's corse and the algea would die off. It did. Now I have very little if any brown algea, and what I do get in the tank the snails take care of easily.
Hope this will help you out.
125 Gal-35 Gal Wet/Dry-Tetra-Tec PF500 HOB
(3) AuquaClear 301 Powerheads-600 GPH
Automatic Tempature Controller
5-6 Inch Sand Bed-200+ lbs of LR