That's interesting. I wonder what it is about the sand that would increase the likelihood of bacterial infections.
mentioned, some bacteria thrive at higher pH/KH. I think that's part of it.
Additionally, I think soil supports more aerobic conditions and a different set of microfauna/bacteria. I think sand requires more work to keep healthy due to compaction.
I also believe their digestive system does better in more acidic conditions, so buffered soil is more forgiving.
Not saying sand doesn't work, but there's a lot more to worry about. I've also struggled to get more sensitive shrimp like blue bolts to breed in sand, so genetic history may play a part too.
For reference, my tap is usually about 50 TDS, between 1-2 dKH, and I have to add CaSO4 and MgSO4 to bring GH up. I target about 130-140 TDS and use RO to maintain.
This is pre-crash from last summer, and I have 18 left from well over a hundred in this 20 long :'(
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