Why do my snails keep dying off?

[jhaggerty1990]

For some reason my snails dont live longer than a month. My parameters are all in acceptable ranges. Salinity stays in range as well. I have a few emerald crabs, golden head goby, and 2 clowns. Idk whats going on, I keep just finding dead turbos or empty nass shells. 25g usually 2 or 3 turbos and 5 nass snails. alk 8 mg 1450 ca 400 0tdsrodi 7.8 ph 1.025 sal. My phos and nitrates did bottom out but now at .03 phos and 10-15 nitrate

 

[TX_REEF]

7.8 ph is pretty low. I'd also say 2-3 turbos is too many for a tank that small. Do they have enough algae/detritus to eat? Emerald crabs may also kill and eat snails if they are hungry, I wouldn't want to have more than 1 emerald in a tank that size (ideally zero because I've seen emerald crabs eat coral too)

 

[Tahoe61]

I don't think chemistry is playing a part. It could be.
1. Predators like Polyclad Flatworms or Pyramid Snails, even the crab
2. Lack of available food sources, as stated 25 gallons is not a lot of real-estate. The Nassarius may need more food.
3. Turbo Snails collected off the Gulf of California and farther south come from colder temperate waters and have a shorter life span in our tropical aquariums.