Even when I added a ph buffer to my r/o water in two days it would bounce back up from 7 to 8.5. I'm not saying this is a short term killer but I found the bounce very stressful for the rays which caused them to stop eating or not eat as much as they should and also made them less and less active over time. This stress could have led to something else.
The hydrogen sulfide could be the killer but seems weird to have a buildup in your sand if it's vaccumed twice a week.
The hydrogen sulfide could be the killer but seems weird to have a buildup in your sand if it's vaccumed twice a week.
. I want to thank everyone for their advice.