There's no "safe range" for ammonia. You want it at 0 or extremely close to it. There are better test kits out there. Test strips are not the best. Anyway, read up and read up some more if you'd like to try at it again. Part of the fun is in the research!
And sorry to hear about your crabs btw.
The ammonia levels are very close to zero, but not quite there. I will get better tests. I have a good ph tester, but the rest of the tests I have are strips.
I appreciate your help. I would really like to have a few vampire crabs, but I feel so bad about what happened that I don't know if I want to try again. I don't want to risk hurting them.
Hopefully the pet store I bought them from can help. I'll stop by and ask them a few questions.
Thank you for your help!