I realize that hydrometers are typically a bit innacurate
IME they are too inaccurate to trust. We sprung for a refractometer before we set up our old 75G, and am thankful that we did. For a system of any size it is invaluable, and they can be found (fairly inexpensive) on eBay all the time. Not aware of LFSs that carry them, but maybe someone else here in Austin knows of one. Sounds like it would be a good addition to your equipment. Do you still have the nano and the pico? Did you get that larger tank you were talking about?

Anyway, if you are still running the nano and pico only, why not just get a refractometer, buy RO/DI, and mix the salt in yourself? That way, you will be sure of your SG, and with small tanks, you won't have to be buying much salt...I'm pretty sure AA sells it in the smaller bags. If you need some SW with 1.025 SG while you are getting these items (if that's the way you decide to go) LUK and we'll be happy to give you some ;)

W.