Welcome to AA!
So, for your questions............
-artificially raising them
-using meth blue(just enough to see a tiny tinge of blue)
-regular tiles in your home work fine.......idk what those ones are(im 14)
clay pots work great
a few questions
how are you raising?
what size tank?
other info? tank stats?
how often WCs?
Are they dying just like that, what stage?
What are you feeding them?
Are they dying because of bacteria/infection