Salinity screw up need to raise my tank from 1.017

[MJV15]

Situation up front, do to my poor selection in refractometers my 90 gal LPS dominate tank is currently sitting at 1.017 and I need to know how much and how quickly I should raise the salinity.

I notice that about 2 weeks ago that my hammer wasn’t extending as much as he had been so I started running tests everything came back normal to the low side on ALK and Cal. So I figure that’s it, so I start dosing my tank. Things still look upset so I do a water change. And it goes on like that until I think to test the ALK levels in my fresh salt and I get 6dkh. Thats when it finally dawns on me to stop trusting my tests. I go to my LFS have them test it and it turns out what I though was 1.027 is in fact 1.017. I should add that I have calibration fluid from Hannah and I have my refractometer “dialed in” at 35ppt which is what the Hannah says it’s at.

I’ve got a couple frags in my tank that are looking pretty rough. So I want my levels to rise but I don’t want to do it so fast that it hurts things.

My current plan is to add 5 gallons at a time of higher constrained fresh salt water. It’s currently mixed to 40ppt. I figured pull 5 gallons out and 5 to the sump every hour or so until things are close to normal again?

my tank DT is 90 gallons
My sump is close to 25 gallons
So call it 115 total system

 

[ReefChef19]

I am not a professional at all, I have done quite a bit of research but still a newbie. With that being said, I personally would just bring it up 2 or 3 points every couple of days so not to shock anything. It has already been this way for a couple of weeks and you haven't lost anything so I wouldn't panic now knowing the information. Here is a link that a friend provided to me to help correct my sanity issue before. I hope everything works out well. Take care

Target Salinity Calculator

Aquarium calculator; Create a water-change schedule that can be used to reach a target salinity.

www.hamzasreef.com

 

[Billldg]

Do you have a ATO, if so then put a few gallons of 1.026 water in it and let it come up over the next few days. If not then top of any evaporated water with 1.026 water. You don’t want to raise it to quickly as this can cause bigger issues. If my salinity has dropped I just use 1.026 water in my ATO and let it come up naturally.

 

[Mical]

+1 @Billldg post. I've had skimmers overflow and ATOs pump gallons of fresh top off water doing the same lowering SG. Just add saltwater to ATO and monitor it weekly, one of the safest ways to bring it up without shocking inhabitants.