Possible to avoid precipitate in stored salt water

[NeverlosT]

In a perfect world, I would store 100g of RO/DI and 100g of pre-mixed saltwater on hand at any time for water changes or emergencies.

However, with both standard IO and ReefCrystals, if I leave the mixed water (circulating) for more than a week or so, I begin to get lots of precipitate and the ALK of the mixture drops dramatically (IO goes from ALK of 10dKh or so down to 7).

For those of you storing pre-mixed saltwater, are there tricks to avoiding precipitate?

I am mixing the water correctly, good temp, a bit of salt at a time, strong circulation, my RO/DI is 0 TDS. The mixture becomes clear and looks great... then two weeks later the parameters are significantly effected.

Things I am considering are:

• Does running an external circulation pump vs. an internal pump affect things?
• Does having a heater present affect things?
• Does the material of the storage container affect things?
• Does the presence of old precipitate in the SW container from the last batch kickstart the precipitation reaction in the new SW batch?

I'd rather not get into a "which salt is better" here, since the salt mixes cleanly and repeatably. The issue happens after a few weeks of circulating in a container. But if someone has factual data that they can share pointing the issue to a property of the chosen salt, I am all ears.

Thanks in advance.

 

[Waters]

I have noticed the same in several different salts (Reef Crystals, IO, and Red Sea). I also heat and circulate. Hopefully somebody can chime in and clarify.

 

[Randy Holmes-Farley Verified Community Expert]

Don't heat or stir.

 

[Randy Holmes-Farley Verified Community Expert]

In a perfect world, I would store 100g of RO/DI and 100g of pre-mixed saltwater on hand at any time for water changes or emergencies.

However, with both standard IO and ReefCrystals, if I leave the mixed water (circulating) for more than a week or so, I begin to get lots of precipitate and the ALK of the mixture drops dramatically (IO goes from ALK of 10dKh or so down to 7).

For those of you storing pre-mixed saltwater, are there tricks to avoiding precipitate?

I am mixing the water correctly, good temp, a bit of salt at a time, strong circulation, my RO/DI is 0 TDS. The mixture becomes clear and looks great... then two weeks later the parameters are significantly effected.

Things I am considering are:

• Does running an external circulation pump vs. an internal pump affect things?
• Does having a heater present affect things?
• Does the material of the storage container affect things?
• Does the presence of old precipitate in the SW container from the last batch kickstart the precipitation reaction in the new SW batch?

I'd rather not get into a "which salt is better" here, since the salt mixes cleanly and repeatably. The issue happens after a few weeks of circulating in a container. But if someone has factual data that they can share pointing the issue to a property of the chosen salt, I am all ears.

Thanks in advance.

The old precipitate may help drive more. I never removed any.

You can lower alk and pH with muriatic acid, which will stop the precipitation.

 

[NeverlosT]

Ok, understood, so if I want to reduce ALK (not rely on precipitation to do so) I can use Muriatic acid.

Also, to reduce precipitation if I want to maintain the ALK of the saltwater mixture, I should not heat the water, and I should stop circulation once the water is initially mixed, and it may help to remove old precipitate.

(That makes sense because when I have removed the pre-mixed water to 5g jugs for storage, it has not precipitated in the jugs).

I'll give these measures a shot. Thank you.

 

[Hitman]

Any update on this? I’m having the same issue with regular IO salt. Been mixing for 4 days as I got busy and there’s a lot of precipitation and a film layer on top of the water.
My setup:
55 gallon tote of rodi
1 Hydor 1350 powerhead
Heater set at 75 as it’s in my basement which stays at 68 all year
Air stone to help with O2 exchange

 

[Mortie31]

I mix and store Tropic Marin reef pro salt fro 3 weeks at a time in my AWC container, I aerate with a small air pump and use a small pump to constantly circulate it. I see no precipitation or any Alk drop that I notice, It mixes to 7.5dkh, could it be salts that have elevated Alk that suffer more in dropping?

 

[Randy Holmes-Farley Verified Community Expert]

I mix and store Tropic Marin reef pro salt fro 3 weeks at a time in my AWC container, I aerate with a small air pump and use a small pump to constantly circulate it. I see no precipitation or any Alk drop that I notice, It mixes to 7.5dkh, could it be salts that have elevated Alk that suffer more in dropping?

They certainly would, yes. It is also very dependent on pH, so if your house has elevated CO2, you’ll likely see less precipitation.