PDA

View Full Version : Mixing salt, general inquiry


gmate
12/22/2011, 10:56 PM
I am mixing salt for my 55g. First time filling tank, so I just filled it up with RO/DI and added a few cups of salt, waited 5 minutes for it to dissolve, checked the SG, added more as needed. Got my SG up to 1.025. Well, I forgot that there's undissolved salts on the bottom of the tank. Obviously I"ll just use my powerhead to stir it up and help it along with dissolving.

But my question is this, the SG of the tank is 1.025 - if I stir and dissolve the salts on the bottom, that'll add to my SG once dissolved, right? So then I shouldn't even bother checking my SG until it's done dissolving?

I know for a water change basis I'd mix in smaller quantities and let it cure over 24 hours because fresh mixed saltwater is caustic, but this is the first time filling and it just occurred to me.

Your input is valued, thank you.

Glenn

sandwi54
12/22/2011, 11:03 PM
if there's still undissolved salt and the SG is already 1.025, once those salt dissolve the SG is going to go up obviously. So yes you shouldn't check SG until everything is fully dissolved. This can take a couple of hours at the most.

however, just because the salt is dissolved it doesn't mean the chemistry is stable. that's why it is a good idea to let the water aerate overnight before use, so that the pH and everything else can stabilize in the water.

sporto0
12/22/2011, 11:06 PM
Yes, the undissolved salt will add to your specific gravity, in the future you will become an expert at mixing water & salt to the proper S.G. In the future remember that salt will not evaporate & top off water & water changes must be monitored to maintain the salinity you want to keep. Good luck & happy holidays.

gmate
12/22/2011, 11:21 PM
Thanks guys. My salinity went up to 1.031 after dissolving the remaining salts. Gonna get some fresh ro/di in there. Thanks all :)