Nyos PURE Reef Salt Mix Struggles

[EEE1986]

Is anybody else struggling to work with NYOS Pure? I just mixed up a fresh batch 4 days ago to around 35ppt using a Tropic Marin Hydrometer and performed a 20% water change. Alkalinity 24 hours after this water change was 8.0. Today I noticed some of my corals were looking off after I returned home from the weekend away. My salinity had dropped from 35 to 33 PPT on my refractometer and my alkalinity dropped to 7.0. I thought maybe my ATO went haywire while I was gone but when I tested the leftover fresh mixed saltwater it alkalinity was 7 and salinity about 1.020 on the refractometer. Another thing that keeps on happening is that when I store the saltwater for over a week it develops an almost moldy smell. I know that this is supposed to be a quality salt but I am really not liking it compared to Tropic Marin which is what I've historically used. I'm wondering if this salt is not made for long term storage once mixed? Perhaps in this last batch I did not mix it well enough (Mixed in a 5 gal bucket with a return pump and powerhead for about an hour)?

 

[mcarroll]

Something about your hygrometer measurements were "off" the first time you measured. (Or both times. Maybe neither is accurate.)

Nothing would make salinity decrease over time.

Alk can drop over time due to precipitation if you are continuously heating and circulating it via pump while in storage. But not salinity.

Do you have an alternate way to measure salinity?

Are you mixing a precise amount of salt mix and water? Start with that...preferentially weigh your ingredients vs using volume measures. But in general, if you carefully measure 5 gallons of water and .5 cups of mix per gallon and mix them together, you will get the correct salinity....you can verify your hydrometer this way. (Randy also has a DIY calibration fluid recipe you can make with table salt and water.....so you have two ways to verify your measurements.)

 

[EEE1986]

Something about your hygrometer measurements were "off" the first time you measured. (Or both times. Maybe neither is accurate.)

Nothing would make salinity decrease over time.

Alk can drop over time due to precipitation if you are continuously heating and circulating it via pump while in storage. But not salinity.

Do you have an alternate way to measure salinity?

Are you mixing a precise amount of salt mix and water? Start with that...preferentially weigh your ingredients vs using volume measures. But in general, if you carefully measure 5 gallons of water and .5 cups of mix per gallon and mix them together, you will get the correct salinity....you can verify your hydrometer this way. (Randy also has a DIY calibration fluid recipe you can make with table salt and water.....so you have two ways to verify your measurements.)

I mix using the exact weight of salt recommended on Top Shelf Aquatics website which is 148–151 grams per US gallon. The only alternate way I have for measuring salinity at the moment is a refractomter calibrated with salt solution I made a month ago measured to 1.0264 using my hydrometer. I keep that calibration solution in an amber bottle with a medicine dropper but I am starting to lose faith in it's accuracy as I just mixed a fresh batch of water overnight to around 1.0259 and it was overshooting this. I do not continuously heat and circulate the stored water.

 

[Fish Fan]

I mix using the exact weight of salt recommended on Top Shelf Aquatics website which is 148–151 grams per US gallon. The only alternate way I have for measuring salinity at the moment is a refractomter calibrated with salt solution I made a month ago measured to 1.0264 using my hydrometer. I keep that calibration solution in an amber bottle with a medicine dropper but I am starting to lose faith in it's accuracy as I just mixed a fresh batch of water overnight to around 1.0259 and it was overshooting this. I do not continuously heat and circulate the stored water.

Just one concern; hydrometers are typically temperature sensitive, my Tropic Marin should be read at 77F to ensure best accuracy. Did you account for temperature when you made your standard solution?

There's a DIY recipe for calibration fluid that's very easy to make using ordinary kitchen salt and a decent kitchen scale or even measuring spoons:
https://www.reef2reef.com/ams/reef-aquarium-salinity-diy-calibration-standards.956/

I would suggest making a batch of this standard solution, and triple checking your salinity. It's so easy and cheap, and then you'll know for sure.

 

[EEE1986]

Just one concern; hydrometers are typically temperature sensitive, my Tropic Marin should be read at 77F to ensure best accuracy. Did you account for temperature when you made your standard solution?

Yes, I have temperature probes and use https://beananimal.com/tools/tropic-marin-precision-hydrometer-correction-calculator/. Temperature probe I used is confirmed well calibrated using ice water bath.

 

[mcarroll]

I mix using the exact weight of salt recommended on Top Shelf Aquatics website which is 148–151 grams per US gallon. The only alternate way I have for measuring salinity at the moment is a refractomter calibrated with salt solution I made a month ago measured to 1.0264 using my hydrometer. I keep that calibration solution in an amber bottle with a medicine dropper but I am starting to lose faith in it's accuracy as I just mixed a fresh batch of water overnight to around 1.0259 and it was overshooting this. I do not continuously heat and circulate the stored water.

The point still stands about physics ad salinity....it won't change on its own....it can only go down if more fresh water were added.

I assume that didn't happen or you'd have mentioned it. ;)

So that means something was wrong with the measurement(s).

I use a refractometer and swing-arm hydrometer from the old days, and have no issues with either one.

Maybe your paper temperature scale in the floating glass unit has moved as another user metioned happened to theirs?

The thing is that you should be able to get repeatable measurements even if they are inaccurate. So keep testing and narrowing down to what the problem is. If you test the same simple in triplicate it might help you see where the problem is better – meaning test, clean up, re-test, clean up and re-test again (three tests) all on the same sample of water or calibration fluid. Tell us what you get as results.

 

[slingfox]

I have been using Nyos Pure for over two years now without any notable issues. I was previously sing Tropic Marine Pro Reef. I mix the Nyos Pure in a 55g barrel which provides me with 3-4 weeks of supply depending on what I am doing on the water change from. I do not notice any notable off putting smell and I am a person who has high sensitivity to odors.