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Algae/Bacteria in Salt Mixing Tub

I did some googling and failed to find much on this besides that you should clean your mixing tub/tank/can/wtv every couple weeks.

Anyways, so I have a 20 gallon Brute container that I use to mix saltwater. I leave a powerhead and heater in there because I don't use that much water, so it sits for a bit sometimes.

What I've started to notice the past week or so is a whitish buildup, looks just like hard water stains, but it's under the waterline. There's also some brown spots that have appeared on the walls and bottom of the tub.

Is this algae or bacteria from the air? How do I prevent this from occurring? I imagine the answer could very well just be clean it more often, but was thinking there might be some preventative measures I could use from now on to combat this as well.
 

ecam

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That is your calcium evaporating from your water.... it happens to my SW mix often when it sits longer then a week or so in the heat...
 
That is your calcium evaporating from your water.... it happens to my SW mix often when it sits longer then a week or so in the heat...

Sorry if this is a stupid question, but how can calcium evaporate underwater? I'm not getting build up above the water, but rather at the bottom of the container mostly.

Also, any sort of light getting in there could cause algae to grow (the brown stuff). Is it covered up?

It's 95% covered. The lid has the wires from the heater and powerhead running under it so it's lifted off the container a bit.
 
http://www.theaquariumsolution.com/brown-deposit-h2ocean-pro-plus-salt
Check that out. I think that is what he was referring to.

Hmmm, not sure if that's what I'm seeing. The brown spots and the white build up are clearly two different things. On the bottom of the container, it just looks like a white hard water deposit, but it's still submerged. The brown spots, I'm 90% that it's algae or bacteria because the way it's forming looks organic and natural.

I do get this dusty off white-brownish coating on my powerhead and heater in there though. That could be what is described in that link, but I use ro/di water so I don't see how heavy metals are getting through and unless the phosphates are leaching from the container, where would it be coming from? The ro/di unit is practically brand new. Unless it's saying that deposit occurs from the stuff in the salt, despite whether or not there is heavy metals or phosphate present in the water.
 
Hmmm, not sure if that's what I'm seeing. The brown spots and the white build up are clearly two different things. On the bottom of the container, it just looks like a white hard water deposit, but it's still submerged. The brown spots, I'm 90% that it's algae or bacteria because the way it's forming looks organic and natural.

I do get this dusty off white-brownish coating on my powerhead and heater in there though. That could be what is described in that link, but I use ro/di water so I don't see how heavy metals are getting through and unless the phosphates are leaching from the container, where would it be coming from? The ro/di unit is practically brand new. Unless it's saying that deposit occurs from the stuff in the salt, despite whether or not there is heavy metals or phosphate present in the water.

How long ago has it been since you gave that container a good clean? Could be particulate just hanging around in there causing the growths that you are seeing. Also, when was the last time you tested the TDS out of the water sitting in a container that you used? I was definitely surprised when I checked mine. I was coming out of the RO/DI at 0 TDS, then in the container, sitting at like 15TDS ish.
 
Its precipitate. Calcium and carbonate. Most mixing containers will get this, its inevitable. If its really bad try mixing the salt a little slower,that help me a bit.
 

ecam

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Its precipitate. Calcium and carbonate. Most mixing containers will get this, its inevitable. If its really bad try mixing the salt a little slower,that help me a bit.

Thanks John. That's the word I couldn't think of.

As for the brown stuff. I assume you are using reef crystals or io. It's notorious for mixing dirty like that.
 
Thanks John. That's the word I couldn't think of.

As for the brown stuff. I assume you are using reef crystals or io. It's notorious for mixing dirty like that.

Yeah, using reg IO. It's been maybe 5-6 weeks since I've cleaned. Which likely is too long, probably shouldn't let it go more than a month, but I was away all weekend, so maybe that's what I'll do this weekend. There is however a clear distinction between the brown, dusty looking stuff that gather on my powerhead vs the darker brown spots that have formed on the container. I assume those must be bacteria or algae of some sort. Does this render my water unsafe for use? I'm due to do a WC today, so I'd like to use the water one last time, then dump it and clean with bleach

And now it makes sense about the calcium. That would be calcite then that's forming on the container? CaCo3? I placed my powerhead down at the bottom and got a larger one to switch out so I'd have one to run in the ro/di container as well. That should help stop things from settling on the bottom, right?
 
I make my water up just after doing a WC, so it sits for two to thee weeks depending on how ambitious I am. If you measure your Ca, Mg and Alk when you first mix it, and then again a couple weeks later, you will see the numbers have come down due to the a biotic precipiation that occurs on the pumps, heaters and sides of the container. Once you have a build up in the container, and add your RO/DI water, the lower pH of the FW will cause some of the calcium carbonate to dissolve and add some TDS to your water. Something that helps during warmer months is not using a heater. I keep my container in the garage, so it'll get cold during winter month's, so I only use a heater the day before I do my WC.
 
Might be a good idea. I keep mine in the basement, so it's typically around 65-72 degrees room temp. Throwing the heater in there only for the day I need it might help. I can't measure Ca, Mg and Alk, as I have a basic test kit for my pretty basic tank. I do a WC every week though, about 5 gallons or 20% and I usually keep like 10-12 gallons mixed at a time in case of emergency That, however, is on the list along with better lighting for when I turn it into a reef tank rather than a FOWLR in a couple months.

Edit: Just took 5 gallons out then dumped the rest. Def some algae or something in there as it was on the airline tubing going to my airstone. Looks like diatoms almost. Brownish colored, was spotty, mostly on the bottom of the container. Everything else was def just precipitate.

Now having just thought to myself, the heater that was in there came out of my tank because it was a bit too big, so I replaced it. Didn't really clean it, just tossed it in and didn't think twice. Could those brown spots be algae that came with the heater?
 
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redfishbluefish

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This is a very common “issue” with salts…..some brands more so than others. It is precipitates from calcium carbonate, clay fillers and/or iron oxides. Here is a picture of an old Tuperware I used for making saltwater…

IMG_0929.jpg


.I now use a Brute which looks similar. When the deposits get so thick they start to flake, I will pour a gallon or so of vinegar into the Brute to clean it up. I use RC and IO and it’s common with these salts.


You can minimize deposits by first assuring you have the full volume of water before adding salt. That is, don’t mix 15 gallons worth of salt when you only have ten gallons of water, with the intent of adding the last five gallons of water later. The higher concentrations of alk/calc will cause precipitation. Also, add you salt like you are salting popcorn. If you just dump the salt into the water, the micro-environment of high concentration will also cause precipitation. Lastly, agitate like he!!. Use the biggest pumps/powerheads you have to mix your salt. When I’m adding my salt, I not only run an old Koralia 4, but also run the MAG 7 I will eventually use to pump out the water.
 
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