This can’t be real- new salt mix disaster

[Errattiq]

Hey all, I went through all my Red Sea blue bucket and I’m finally tapping into the boat load of live aquaria professional reef salt that I bought last year during their Black Friday sale. I’ve been doing this for 15 years, never have I encountered such horrendous precipitation in my newly mixed saltwater. I’m assuming it’s calcium precipitating out of solution but I’m open to suggestions for those that have dealt with this. The salt mixes clear in my 32 gallon brute container, then a few hours later the water gets extremely cloudy and stays that way. When I tested the water, it shows alkalinity at 6 and calcium just shy of 400 via my Salifert kits. This residue has already jammed the impeller of my mixing pump once, I’d hate to toss 5 boxes of this stuff but I don’t know what else I can do. I add the suggested amount of salt exactly as the directions indicate and I’ve even resorted to adding it over the course of many hours just to make sure the calcium wasn’t precipitating because it was added too quickly. I have the same result each time. I’ve included photos of what’s left over in my mixing container. Any clue?

 

[xxkenny90xx]

Weird, I went through one 200g box of that stuff maybe a year ago and didn't have that issue at all. Maybe you got a bad batch?

 

[Mical]

That is bizarre. The only thing that comes to mind (some say it happens others say it doesn't) Did you mix the salt in box/buckets prior to adding it to water? There have been claims in the past that the ingredients settle and separate after sitting for long periods. BRS last year said they didn't believe that but as an old time reefer taught me ALWAYS mix the salt in bucket/box first and add salt to water - not water to salt.

 

[Greenreef75]

I had the same problem with a bunch of reef crystals that I bought on sale after they sat in my garage for a while. I think it may have been the heat and humidity

 

[Sebastiancrab]

I had the same problem with a bunch of reef crystals that I bought on sale after they sat in my garage for a while. I think it may have been the heat and humidity

So is it unwise to store your salt in a hot garage? That is where mine is now.

 

[Greenreef75]

So is it unwise to store your salt in a hot garage? That is where mine is now.

I won’t be storing it like that long term anymore

 

[Errattiq]

I appreciate the replies thus far, I always turn my salt over to prevent issues from settling during shipping and storage. I never, ever add water to my salt. I add my salt slowly via a 1 cup container into my 32 gallon brute container filled with RO/DI (0 TDS) water that is being churned by my DC pump. I also have a maxijet aimed at the bottom of the container to make sure no salt settles on the bottom and stays in suspension so it all gets evenly mixed. I add the salt over the course of a few hours and once at 1.026 as read by my calibrated automatic temperature compensated refractometer, I add my heater and bring the temp to 78 and per the instructions on the container, allow 2-4 hours for pH to stabilize before adding to the system. Problem is, during this 2-4 hour “stabilization” period that’s when the water clouds up and basically becomes unusable.

 

[PBnJOnWheat]

I appreciate the replies thus far, I always turn my salt over to prevent issues from settling during shipping and storage. I never, ever add water to my salt. I add my salt slowly via a 1 cup container into my 32 gallon brute container filled with RO/DI (0 TDS) water that is being churned by my DC pump. I also have a maxijet aimed at the bottom of the container to make sure no salt settles on the bottom and stays in suspension so it all gets evenly mixed. I add the salt over the course of a few hours and once at 1.026 as read by my calibrated automatic temperature compensated refractometer, I add my heater and bring the temp to 78 and per the instructions on the container, allow 2-4 hours for pH to stabilize before adding to the system. Problem is, during this 2-4 hour “stabilization” period that’s when the water clouds up and basically becomes unusable.

Whenever I mix Red Sea coral pro salt, it leaves. A residue typically so I think it’s normal but... maybe not?

 

[Errattiq]

Whenever I mix Red Sea coral pro salt, it leaves. A residue typically so I think it’s normal but... maybe not?

Yea the residue left behind from the Coral Pro salt and this are two entirely different beasts. Whatever this residue is clouds the newly mixed saltwater terribly and stays that way

 

[Cell]

Fwiw, I used the LA salt from the same sale last year for about 6 mo and experienced no issues like this.

 

[vetteguy53081]

I had good luck with their mix
What was age if the salt?

 

[Randy Holmes-Farley]

Folks are often concerned about precipitation, but there's no great concern (IMO). Most high alk mixes do it. Higher alk and higher pH will do it.

As long as the alk in the mix is still Ok for you, it is good to go.

I discuss such precipitates here:

What is that Precipitate in My Reef Aquarium? by Randy Holmes-Farley - Reefkeeping.com

specifically here:

http://reefkeeping.com/issues/2005-07/rhf/index.php#2

Figure 1. The residue on the bottom of the plastic trash can that I use to mix Instant Ocean. I rarely clean it out. The solid is most likely calcium carbonate.

Solid Residues Remaining After Preparing Artificial Seawater
Most salt mixes leave behind a solid residue when dissolved, although the extent to which this occurs varies from brand to brand. I use Instant Ocean and rarely clean out the 44-gallon trashcan that I mix it in, so a significant residue builds up over time (Figure 1). In preparation for this article I removed some of this solid material, and found that it could be almost completely dissolved in hydrochloric acid with lots of bubbling. This demonstrates that these solids were probably calcium carbonate (CaCO3), perhaps also containing magnesium. Pure magnesium carbonate is undersaturated in seawater (which is detailed in later sections of this article) 1 and should dissolve in marine systems, so it isn't likely to be the precipitated material, although there may be significant magnesium in the calcium carbonate.

Based on the fact that the material exists as sheets that clearly did not arrive in the mix (as opposed to a fine powder which might have), I conclude that at least a significant fraction of this residue formed in the barrel. I cannot, however, rule out the possibility that some solid calcium or magnesium carbonate may have existed in the salt mix and was cemented together by additional precipitation of calcium carbonate during dissolution or storage.

When salt mixes are dissolved, there exist local regions where the salt concentration is very high. In those local regions, the calcium and alkalinity must also be very high. In fact, as seawater is concentrated by evaporation, there is a well-established series of minerals that precipitate as the salinity increases. In this series, calcium and magnesium carbonate are the first to precipitate, appearing at a specific gravity of about 1.140, which is about a 50% solution of salt in water.1 Such conditions may well exist on the bottom of a saltwater reservoir as the salt is dissolving.

With some mixes (but not the Instant Ocean that I use), the initial pH on dissolution may be very high (pH 8.5-9 +). As shown in detail later in this article, pH can play a dominant role in determining the rate of calcium carbonate precipitation, and such a high pH would make it more likely to precipitate.

It has been suggested by some aquarists that some salt mixes may contain anti-caking agents, such as clays. I do not know if this is true, but if it is, they may form part of the residue that is left behind after dissolution.

In order to minimize the formation of insoluble carbonate salts when mixing, the following suggestions may be helpful:

1. Add the salt to a full batch of water, rather than adding water slowly to a large batch of salt. The latter allows a greater time at much higher than natural seawater salinity, which may tend to precipitate calcium and magnesium salts.

2. Stir the mixture vigorously as it is being dissolved.

3. If using a mix with a high initial pH, aerate the mixture as well as stirring it. The aeration will reduce the pH.

 

[Randy Holmes-Farley]

Yea the residue left behind from the Coral Pro salt and this are two entirely different beasts. Whatever this residue is clouds the newly mixed saltwater terribly and stays that way

That is likely just an effect of particle size of the precipitate. Fine particles will be slow to settle out.

 

[Randy Holmes-Farley]

You didn't use tap water, did you?

The alk that can be in tap water may push the mix too high.

 

[Clownfish_Boy]

Use only Instant Ocean salt.

 

[ImGoingCoastal]

I always thought it was best practice to bring the water up to temp BEFORE adding the salt. Maybe give that a try?

 

[andrewkw]

The salt mixes clear in my 32 gallon brute container, then a few hours later the water gets extremely cloudy and stays that way.

Is this perhaps one of those salts that you are supposed to use immediately after it goes clear? Normally I use IO but on occasion I do get other salts. I got a bucket of Tropic (not tropic marin) and it says to use 20-30 minutes after mixing.

 

[Randy Holmes-Farley]

I always thought it was best practice to bring the water up to temp BEFORE adding the salt. Maybe give that a try?

Precipitation of calcium carbonate happens more at higher temps than at lower temperatures. It is one of the chemicals whose solubility declines with increases in temp.

 

[Cell]

Is this perhaps one of those salts that you are supposed to use immediately after it goes clear? Normally I use IO but on occasion I do get other salts. I got a bucket of Tropic (not tropic marin) and it says to use 20-30 minutes after mixing.

I never really understood this. How is the saltwater circulating in a container different than the same saltwater circulating in the tank. Somehow the extra nutrients in the water stabilize it or something?

 

[Randy Holmes-Farley]

I never really understood this. How is the saltwater circulating in a container different than the same saltwater circulating in the tank. Somehow the extra nutrients in the water stabilize it or something?

Yes.

Organics and phosphate are very good at stopping abiotic precipitation of calcium carbonate from seawater. They are absent in salt mixes. They get onto the growing crystal surface and block further precipitation.

Corals, in fact, control the shape of skeletons using organics to control where precipitation takes place.

In an experiment I did long ago, i found I was able to push alk super high in tank water if I added an organic designed for that purpose (sodium polyacrylate). The idea was that one might be table to keep a tank (or coral farm) at, say 20-30 dKH, and possibly get far faster growth of hard corals. I never tested it out with corals.