What can I do to get it up and why is it that it is fine in the trash can but once we did a water change it is gaone again
When you mix it at a higher sg, and add it to water of a lower sg, the sg of the tank will raise, but won't be as high as the water you added. Make sense?
Well,I know that we added salt cause it was our first time to ever do it...lol
What was the sg of the water you mixed to add to the tank? If it was too low, that would cause the sg in the main tank to drop.
The star won't show signs of stress right away, trust me on this. Keep a close on him. It may even be a few weeks before you see a problem with the star. Depending on how long the sg has been this low, and how slow you raise it.
IME, what would cause this is if the guy did water change with just water, and forgot to add the salt, or did the water change a lower sg than the tank, not adding top off water would make the sg high, not low. Not doing a water change would just mean possible high nitrates... Did you test the water before moving the tank? (wondering if water was lost and ro water was added in place of saltwater...). If the fish/inverts have been at alow sg for awhile, they are used to it, but it's still stressful.
HOWEVER, please have lfs test your water or buy another test (even if you just take it back)
My qt tank =1.021 and my main tank is 1.017
Both levels are DEADLY to stars and inverts. Slowly raise your sg up to 1.025 or so, if you do it too fast, you'll shock the star... mix your water, let it sit, I'd mix it higher than 1.017, but I don't know how much higher.
I had to slowly raise my sg level, I mixed salt to my top off water at the sg I wanted, so about a gallon a day, I guess? I think I also did a water at a higher sg. I really don't remember. Please do a search on the proper way to raise the sg.
Good luck, if the fish/inverts show signs of stress, keep the lights off.