At what rate can I safely lower salinity.

[Cunning_plan]

If I plug your info into hamz reef, this is even what it says to do



FYI: You can find this calculator and many other helpful ones at :

Target Salinity Calculator

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

www.hamzasreef.com

There is probably a clever reason it wants me to use larger quantities of mixed salt rather than smaller quantities of RO/DI but I'm not seeing it... I doubt I even have enough salt for that proposal! I see a lot of water changes in my future.

 

[Miller535]

There is probably a clever reason it wants me to use larger quantities of mixed salt rather than smaller quantities of RO/DI but I'm not seeing it... I doubt I even have enough salt for that proposal! I see a lot of water changes in my future.

No, The scenario I included in the picture is using 0ppt water (RODI). No ssalt needed

It is essentially having you take 1 gallon our, and replacing it with 1 gallon of RODI water and giving you about a .8ppm drop. So 1 gallon with RODI would drop you to 49.2 from 50 and so on.

 

[William Mumford]

In Short:
I have salinity at 45+ ppt. How can quickly can I take it down to 35? Should I be water changing with RODI water or low salinity water.

In Long:
I have been running a reef tank for around 5 months now. It's a reefer 250 (55g). Over time I have gradually tried to add corals. With a few minimal exception these have all died. As it stands living I have 2 GSP frags, a kenya tree frag, and 5-6 very closed up zoas. I also have a couple of cleaner shrimp, a convict Blenny, 2 small clowns, a lemon damsel and a firefish.

Over the past 3 months I have tried adding corals 4-5 times. In some cases they have done fairly well, I had a hammer and an elegance coral that seemed to be thriving for a while. In others though, they just died. The few SPS frags I tried to add died within 12 hours. No zoa has ever opened more than 1/3 of the way. In response to this, I tinkered far more than I should have. In terms of flow, placement, lighting and nitrate/phosphate removal. I always assumed it was my basic chemistry but on multiple test kits showed 0 Amonia/Nitrite and close to zero Nitrate/Phosphate. Salinity always showed around 33.

Given my salinity had always been a touch low, I decided that could be my cause. Over the course of 2 weekly water changes I raised it from 33-35. At that point what few corals had been prospering died.

At that point I almost completley gave up. I was on the verge of just keeping fish. But I read online about people with the same refractometer as I have having to calibrate it frequently. Having never done this I decided to give it a go. I bought a 35 ppt test solution and put it into my refractometer. It came out as 20. Assuming I had a bad batch, I ordered a second sample from a different brand. 20. Reading online I saw that a lot of people simply calibrate to RODI water. I tried that. -15. It was so out, the calibration dial wouldnt even let me correct for it.

So here I am. I've ordered a new refractometer which should come tommorow. But I need to work out what to do. My salinity is currently running somewhere in the 45-50 range. What are my next steps?

As a small aside, I realise that I have made almost every clasical rookie mistake possible here short of adding 3-4 tangs to my tank. My aim once this is sorted out is just to run the whole thing stable for a month or so before doing anything else.

Do you have an Auto top off?

 

[Cunning_plan]

Do you have an Auto top off?

Yes?

 

[code4]

Fish are really tolerant of drops in salinity. That being said no matter how you decide to go forward get out some RODI water and get it the current temperature as in your DT and start lowering the current salinity. I might have missed it but I did not see how large of a system you have. The larger the system is the larger amounts of water you can change without seeing any difference.. And the longer it is going to take to get it down. Good luck

Shelley

 

[William Mumford]

Yes?

Do know where is the rise coming from?

 

[Reef.]

Do know where is the rise coming from?

he never calibrated his refractormeter.

 

[Cunning_plan]

he never calibrated his refractormeter.

To be fair, even fully turning the dial won't bring it into calibration. But yes, the stupidity of this is painful.

 

[plankton]

most salt mixes given general instructions like 'add half cup of salt per gallon of ro/di to make 1.02x specific gravity water'. So, if you know how many cups of salt you are adding per gallon on water then you know roughly what your salinity is (for your salt mix). +1 on taking sample of your water to a LFS or friend for second opinion before you plan any major changes.

 

[Randy Holmes-Farley]

I do not know how fast to drop it is best, but I personally would spread it out over, say, a week.

 

[Stigigemla]

I drop or rise max 1ppt up to 2 times a day. Even with that small changes some corals react. Strangely Sinularia seems to be the most sensitive by me. Having a top off I just take water and let the top off do the dilution.
Just have to be careful to refill the top off container.

 

[Cunning_plan]

Just for anyone looking at this in the future. I dropped the salinity from 50 - 35 in 5 water changes using RODI water. I did this over the course of 5 days.

In terms of impact, I had one of my clowns take a jump. The only surviving corals were the ones hardy enough to have been at 50 ppt salinity for months so were fairly unbothered. A few of my zoas are very slowly starting to open now, some are still fully closed.

I'm now working to sort out the rest of my water chemistry and plan to run it stable for a month or so before working out what's next.

 

[Randy Holmes-Farley]

Thanks for the update.
Good luck!