Mystery Snail Cleanup Crew

Hi everyone - I have a long-established 90 gallon freshwater currently populated with 6 Denison Barbs and 2 Angels. I'm looking to add a clean-up crew and am considering Mystery Snails. At one point in time, long before this aquarium, I had some but they didn't seem to survive for long. So, I want to make sure I prepare for their potential addition.

With a quick Google search I found they need: pH level between 7.6 and 8.4, a temperature range of 68°F to 84°F, and hard water with a kH (carbonate hardness) between 12-18.

Temps should be good in my aquarium but I need to remeasure the exact pH and hardness again since it has been a while. Any other advice or considerations?