bit of a percipitation problem with water changes

[Metal Man 1221]

Hello all

It seems that recently when doing my water changes Iv been getting very cloudy batches of water and later getting a build up of precipitate on the glass

Now I know this is linked to high pH if the salt is added too quickly, however, I add my salt slowly over the period of a few hours and usually aerate for at least 24 hrs

Im just looking for any input on the situation, I use IO btw

Thanks

[HighlandReefer]

Many of the salt mixes are pushing the alk, calcium and mag levels up much higher now, which can possibly lead to a little precipitation of calcium carbonate. Every once in a while hobbyists run into batches of salt mix with unusually high alk levels, which could possibly cause the precipitation. Possibly your equipment used to measure salinity is off and your salinity is much higher than you think. Just a few possibilities I can think of off hand. ;)

[Percula9]

Try a different salt?

[TripleT]

Are you stirring up something in the tank during your changes?

I'd try mixing the new water for a longer period, just to see if it has any effect.

Is the container you're mixing water in clean to start with?

Are you adding anything other than salt mix?

Have you tested the newly mixed water prior to adding it to your system?

You might bring some water samples to your LFS as a sanity check.

[bertoni]

IO should mix to a reasonable pH, but if you're seeing precipitation, I'd aerate it long enough for the pH to be in the normal zone. I tended to aerate the saltwater overnight, which was more than long enough. I agree that the salt mixes are pushing the parameters higher. What are the parameters in your tank?

[Metal Man 1221]

Many of the salt mixes are pushing the alk, calcium and mag levels up much higher now, which can possibly lead to a little precipitation of calcium carbonate. Every once in a while hobbyists run into batches of salt mix with unusually high alk levels, which could possibly cause the precipitation. Possibly your equipment used to measure salinity is off and your salinity is much higher than you think. Just a few possibilities I can think of off hand. ;)

Thanks Cliff, ill have to see if my hydrometer is accurate

Try a different salt?

I dont really feel like switching for such a small issue


Are you stirring up something in the tank during your changes?

I'd try mixing the new water for a longer period, just to see if it has any effect.

Is the container you're mixing water in clean to start with?

Are you adding anything other than salt mix?

Have you tested the newly mixed water prior to adding it to your system?

You might bring some water samples to your LFS as a sanity check.

1. no nothing is getting stirred up, i use a 20 gal AGA tank

2.I have been leaving the batch to aerate longer but i still have the issue of precipitation right away, which would be fine other than the fact that i have to clean my mixing pump and tank after every water change

3^ yes, i clean the pumps and tank after every WC

4. no, i havnt tested it recently just because iv never really had a problem with it, however im thinking its a bad batch


IO should mix to a reasonable pH, but if you're seeing precipitation, I'd aerate it long enough for the pH to be in the normal zone. I tended to aerate the saltwater overnight, which was more than long enough. I agree that the salt mixes are pushing the parameters higher. What are the parameters in your tank?

Yes, im thinking that aerating for longer will bring the pH into normal range and clear the water, the only problem, like i said, is that there is still that initial imbalance which precipitates quite a bit of calcium carbonate on to the tank and pump, which is the problem im trying to solve

[HighlandReefer]

Running your salt mix through a filter sock would help eliminate precipitates from entering your tank. We can see particles down to around 60 - 70 microns in size, so a filter sock with that pore size or less would help the most. Filter socks are cheaper than wasting salt mix. ;)

I would check the parameters of your fresh salt mix. If your lfs has a properly calibrated refractometer, you can use this to check your hydrometer and calibrate it.

[Metal Man 1221]

Running your salt mix through a filter sock would help eliminate precipitates from entering your tank. We can see particles down to around 60 - 70 microns in size, so a filter sock with that pore size or less would help the most. Filter socks are cheaper than wasting salt mix. ;)

I would check the parameters of your fresh salt mix. If your lfs has a properly calibrated refractometer, you can use this to check your hydrometer and calibrate it.

A filter sock sounds like a great idea, I don't know why I didn't think of that, however, my thoughts are: would adding vinegar be sufficient in dropping the pH enough to redissolve any particulate matter back into the water? That way there is a carbon source for bacteria at the same time.

Unfortunately my hydrometer is a crummy old IO brand and I doubt if it could be calibrated, but I found a local hobbyist to purchase a refractometer from.

Thanks again Cliff

[bertoni]

Vinegar can dissolve calcium carbonate, and probably most of the precipitation. What plan did you have in mind?

[Metal Man 1221]

Vinegar can dissolve calcium carbonate, and probably most of the precipitation. What plan did you have in mind?

Well I dose vodka for bacteria and have had good luck with it. Now I was thinking I might be able to switch to vinegar, only add it to my salt mixing tank slowly as I add salt hoping to keep the initial pH low enough to prevent any calcium carbonate precipitation. Then once I have my salt added, begin aerating to stabilize the pH before adding to the tank

Iv also heard of adding a cup of tank water to a fresh salt mix to help boost bacteria levels, which might be a bonus in my case with having a carbon source added as well.

[bertoni]

Adding vinegar to the salt mix might help a bit with precipitation, but then the vinegar will begin to decay, which makes it less useful for carbon dosing. I'd ignore the precipitate, personally.

I don't think there's much benefit to adding tank water to the freshly-mixed saltwater. There's not many bacteria in our tank's water columns, and I'm not convinced there's all that much food for most bacteria in the salt mix. There is some ammonia, that would feed nitrifying bacteria, but unless the salt is going to be stored for a couple of weeks, or some long period, there won't be much chance for the bacteria to grow to a significant population. The process is a lot like starting a tank with no live rock, and then adding some ammonia.