Salinity Swings

Taiko713 · Dec 17, 2020

Firstly, thank you all for any info or advice that may help me understand what just happened.

I have a 90 gal reef tank, with a Trigger Ruby 34 gal sump. Running an ATI 6 bulb T5 fixture with one Blue ReefBrite strip; 2 Tunze 6055s, 2 small poweheads (constantly on) along the bottom back, Reef Octopus 110 int skimmer, Current USA eFlux return pump; all mostly running through Apex EL. There is about 125# of live rock, 60# of live sand, 15 fishes, some inverts and mixed reef. Had a rainbow split, so now I have 5 that are growing quickly. (3 are about 3"-6")

I was performing regular water changes up until recently. I would alternate from 10-15 gals one week to 5 the next. I then started to push that to every two weeks. However, this last week my salinity shot up for no apparent reason. (Apparent to me at least.). The tank went from a 1.026 (constant) to a 1.030 in a matter of days. I unplugged the Tunze ATO about a month ago, cause I'm moving some things around, but still kept up with the 1 gal per day of evaporation. I don't think that i didn't put in more seawater during the daily top off, cause I keep RODI in clear 5 gal containers and the natural seawater in blue ones.

The only thing that i can think may have occurred is that they messed up on one of my tanks at my LFS during refill. Any insight you folks may have is greatly appreciated.

Thank you

Hydrored · Dec 17, 2020

salinity won’t go up that fast if keeping up on top ups, my guess is you are right that they may have mixed up the water. Anymore water in the jugs to test with a refractometer? Any reason you are not making your own water? How often are you testing salinity?

vetteguy53081 · Dec 17, 2020

What instrument are you using to test the salinity?
Are you testing the tank before adding new water? Obviously if salt is high add water only and if low, add salt water

laverda · Dec 17, 2020

Dosing two part will increase your salinity.

Taiko713 · Dec 18, 2020

laverda said:
Dosing two part will increase your salinity.

I've been dosing Seachem Reef Fusion 1 & 2

Taiko713 · Dec 18, 2020

vetteguy53081 said:
What instrument are you using to test the salinity?
Are you testing the tank before adding new water? Obviously if salt is high add water only and if low, add salt water

Using standard refractometer. Never test new water cause I never had an issue. I took out 2 gals of tank water today and replaced with RODI which brought it down to 1.028. I'll do a 20 percent water change tomorrow and bring it back down to where it should be with mixing in more RODI in to .

Good news is no fish or coral have expired. I hope it's cause I caught it it in time.

Taiko713 · Dec 18, 2020

Hydrored said:
salinity won’t go up that fast if keeping up on top ups, my guess is you are right that they may have mixed up the water. Anymore water in the jugs to test with a refractometer? Any reason you are not making your own water? How often are you testing salinity?

Live in Miami and have always used natural seawater except when I started up the tank. That was the only time I ever mixed salt water or used a saltwater mix. I could buy either from my LFS, but because I never had an issue, i never went with the mixture. ( I believe they use Red Sea)

Are there any advantages in using one over the other?

Thanks

Randy Holmes-Farley · Dec 18, 2020

The rise can only be test error, or inadequate replacement of evaporated water. To get that rise, the water level would have had to drop substantially, and I don't expect that happened.

The two part did not boost the salinity like that in 4 days.