Mixing fresh salt water

[dmatt56]

Hello everyone

 

Do any of you ever experience a white precipitate in freshly mixed saltwater when adding too much salt to the RODI water? I am guessing that it is calcium or alkalinity. If yes do you typically use this saltwater or you makes new saltwater? Is there any way to make the precipitate mix back in with the fresh saltwater?

 

Thanks

Matt

[Origami]

Yes, it's likely carbonate salts - calcium and magnesium carbonate. It often comes from too much salt added too quickly. If allowed to sit in a condition of oversaturation for too long (without adequate mixing), it can begin to precipitate out.

 

Another possibility to explain what you're seeing is that the salt was not well protected from humidity and the carbonate salts have begun to precipitate out while still in the container. When you add salt like this, the precipitate does not dissolve, but ultimately settles.

 

Finally, sometimes I'll get a gray to gray-brown "plating" in my salt-mix container. Mostly carbonate salts with impurities, I think.

 

Oh, and no. It won't go back into solution unless you lower the pH with something like an acid.

[icecool2]

I get the same thing. It usually dissolves away after a few hours, but I also add some vinegar to my new water and that helps dissolve things too.

[.OptimusPrime.]

Glad to know im not the only one with this issue.

 

 

Finally, sometimes I'll get a gray to gray-brown "plating" in my salt-mix container. Mostly carbonate salts with impurities, I think.

 

 

I have this going on right now in my 20G mixing brute trash can. I haven't seen any ill effects from this, but then again I'm running fallow with just snails.

 

Do you clean yours out with anything to get rid of the plating or just leave it as is?

 

Also, mine seems to have a stench to it if I close the lid, but if I leave the lid open no smell.

[Origami]

Glad to know im not the only one with this issue.

 

I have this going on right now in my 20G mixing brute trash can. I haven't seen any ill effects from this, but then again I'm running fallow with just snails.

 

Do you clean yours out with anything to get rid of the plating or just leave it as is?

 

Also, mine seems to have a stench to it if I close the lid, but if I leave the lid open no smell.

I've never had any problem with it and cleaned it out once in 3 years of use, just because I was looking for something to do.

 

I've never had a bad smell coming from it, though. Do you run a pump in your water to keep it turning over? If not, you may be developing an anaerobic area deeper in the reservoir that is ultimately releasing hydrogen sulfide (smells like rotten eggs). I run a pump on a timer - it goes off for 30 minutes every four hours - for this purpose. You could also use an air pump and air stone, but this causes salt deposits near where the bubbles pop.

[Ryan S]

Glad to know im not the only one with this issue.

 

I have this going on right now in my 20G mixing brute trash can. I haven't seen any ill effects from this, but then again I'm running fallow with just snails.

 

Also, mine seems to have a stench to it if I close the lid, but if I leave the lid open no smell.

 

My 20g brute has the brown film on the sides as well, plus the smell when the lid is on. I have wondered if this would cause any ill effects as well. I haven't seen any yet though. And the smell does goes away once you remove the lid for a little bit. I run a pump 24/7 mixing the salt.

Edited July 11, 2012 by Ryan S

[.OptimusPrime.]

I've never had any problem with it and cleaned it out once in 3 years of use, just because I was looking for something to do.

 

I've never had a bad smell coming from it, though. Do you run a pump in your water to keep it turning over? If not, you may be developing an anaerobic area deeper in the reservoir that is ultimately releasing hydrogen sulfide (smells like rotten eggs). I run a pump on a timer - it goes off for 30 minutes every four hours - for this purpose. You could also use an air pump and air stone, but this causes salt deposits near where the bubbles pop.

 

I wouldn't say its as bad as rotten eggs, but its close. There have been a few times where I have let the water go stagnant after the salt was mixed. Maybe a day or two before I turned the pump back in to use. I have made it a point recently to keep the pump running until I need the water, but still tends to stink with the lid on.

 

Do you think cleaning will help? I have tested the water for TDS and it reads 0.

 

And sorry OP didn't mean to hijack your thread.

[jaddc]

The precipitation won't cause any harm, but it does decrease the total salts in solution, obviously. Some goes back into solution, most does not and will settle out to the sides and bottom. Any smell, is probably algae or bacteria munching away (this doesn't appear to be harmful). My guess is that the algae/bacteria are attached to the sides, so most of it does not get into our tanks.

 

To minimize the precipitation when making saltwater:

1) Make sure your RODI water is at least room temp (>70 degrees) (since fresh RODI comes from the cold water tap)

2) Start agitating your RODI water with a power head just before you add salt, not after.

3) Add salt slowly and distribute it over the entire surface. You don't have to wait until it dissolves, but wait at least 10 secs between additions to let it distribute. I add my salt in thirds. This minimizes local saturation. Think of cooking -- when baking, one does not add all of the dry ingredients to the wet ingredients at once.

 

Once precipitation starts, it will continue to some degree (like rock candy). So keep it agitated and at least 70 degrees until you use it.

 

That all said, many people just dump in their salt, precipitation be darned, mix it up, and have beautiful tanks.