A lot of snails you get are small and even with Reef Cleaners diverse gallon specific packages it comes out to way more than 1 snail a gallon. A 50 gal diverse clean up crew package there are right at 100 different snails in it, that’s not even including the crabs. Many of the dwarf ceriths and other varieties included are very tiny which is good because they can get to those hard places big ones can’t, and they are very generous with the smaller snail counts. I’ve always had good luck with them on multiple different orders besides one.
I lost an urchin and a couple Halloween crabs on an order when that UPS plane crashed in Kentucky last year. My order was on a flight that was at or going through that airport and it got delayed/diverted by like 36 hours, but that wasn’t their fault.
I just had a massive snail hatch in my tank and I have a 4 x 2 x 2 tank and you couldn’t throw a dime in there at night and not land on a half dozen of them when the lights go dark. There has to be a minimum of 800-1,000 freshly hatched snails (ball point pin head size now) in my tank and I already have at least 100 mature snails of different varieties throughout my tank and sump
You see a lot of algae issues on this forum and I think a lot of people underestimate how many/variety of snails it takes. A couple pics of my newly hatched army starting to come out of hiding and grazing before the lights are even off. Don’t know what kind they are yet as I can’t tell. The rock work gets absolutely carpeted with them, they are on and in everything. I’ve had a solid Trochus snail hatch before but this one dwarfs that one.