Help, corals closing up

[Ty Hamatake]

I always get my water from the same fish store and they always double check it's at 1.025 before I leave and I top off with fresh water. So I doubt my refractometer is that much off or my salinity is that off. But how can I calibrate my refractometer at home if I don't have RO water on hand? Can I use distilled?

I'd suggest using this https://www.bulkreefsupply.com/aqua-craft-refractometer-calibration-fluid.html
You'll want to calibrate as close to the level you're shooting for as possible to reduce the affect if any calibration discrepancies on your end results.

I usually just use purified water with prime. Is that bad?

If it's truly purified, then Prime isn't needed. I would have to suggest the same as @saltyfilmfolks and go for the RODI.

Also (just double checking), your alkalinity is 2.96 meq/l?

 

[Natashamarie]

I'd suggest using this https://www.bulkreefsupply.com/aqua-craft-refractometer-calibration-fluid.html
You'll want to calibrate as close to the level you're shooting for as possible to reduce the affect if any calibration discrepancies on your end results.


If it's truly purified, then Prime isn't needed. I would have to suggest the same as @saltyfilmfolks and go for the RODI.

Also (just double checking), your alkalinity is 2.96 meq/l?

Yep that's correct