10 gallon aquarium stocking

Hi(:
I have a 10 gallon heated & filtered aquarium that currently houses a female betta, 3 small corycats, and 2 african dwarf frogs. I had a snail in there, as well. But it died. I've never really had good luck with snails, not too sure why. But I was wondering if I could add one more african dwarf frog in?
According to AqAdvisor, that would put my tank at 98% stocked, is that bad? I've heard good and bad things about that website.
Would my tank be overstocked, or would it be okay?
thank you

this is a slightly old thread but I'm going to bump it up anyway because I have some thoughts.

1 - if your snails are dying, you are not feeding them properly/might not have good water quality.

2 - 3 cory cats is too few. They need groups of 5 or more.

3 - african dwarf frogs are fine, but are you SURE that's what you have? If you bought it from petco or petsmart you probably have an african clawed frog, which are aggressive, and should only be kept 1 per tank.

4 - 98% stocking is irrelevant, you should be looking at what your filtration capacity is. AqAdvisor is not the end-all be-all advice website, you need to do more research.

Make sure you get a master freshwater test kit and test your water. Make sure you have good readings, and then maybe try a snail again instead of another frog.