Old shell growth always erodes first--the protective protein layer has had the most time there to get beaten down so it doesn't protect against low Ph. I distinct improvement in new shell quality means you're on the right track
BTW not sure what powder you're using, but baking soda can also be used to raise Ph very effectively in freshwater snail tanks. Test the amount needed on a bucket of water, and just make sure it's good and dissolved in a cup of tank water before you poor it in.
BTW not sure what powder you're using, but baking soda can also be used to raise Ph very effectively in freshwater snail tanks. Test the amount needed on a bucket of water, and just make sure it's good and dissolved in a cup of tank water before you poor it in.