Increasing specific gravity

[greg_keyser]

I've had my 50 gallon reef tank for over 3 years now, and my specific gravity has slowly sunk to about 1.021. I'd like to get it back up, and was planning to do the following: Each time I add water that has evaporated off (about 2.5 gallons every 10 days) I will add salt water instead of fresh water until the SG gets back up.

Questions

1. Does that sound like a good plan?
2. What specific gravity should I mix the added water to? I'm thinking 1.025.

Thanks,

Greg

 

[Marty M]

Hi Greg,
That is exactly what I have done, but my system doesn't evaporate very much, so it was a little slower. If you top off with water that is approximately the same as the tank, the s.g. will still increase, but at the rate of evaporation which is more gradual. Some individual corals may not look their best during the process. You can slow it down a little until they adjust, if they seem too stressed.
Have you heard about the Puget Sound Aquarium Society? http://www.fitermania.com/psas/
I've been to four meetings and seen some awesome systems. I picked up quite a few frags and a lot of info too. There is a meeting next week.