Long-term saltwater storage

[StrikerKratos]

I will be setting up an automatic daily water change system. This thread will be mainly discussing the effects of long-term storage vs water chemistry in artificial saltwater.

Salt I am using: Regular Red Sea Salt (not Coral Pro).

I won't get too into this part as this thread is for chemistry, but...

Equipment: Three 55 gallon drums, one new saltwater, one old saltwater, one RODI. Each drum will have a Mag 2 pump, the drums are blue and USP (United States Pharmacopeia) grade. The drum will have a minimum level as not to burn the pump, this will leave at least 45 gallons of water. At 2 gallons a day, this will last about 22 days.

I have a Hydor 565 powerhead to keep the saltwater slowly moving, mixing is done by the Mag 2.

I will be tracking the following:
- Alkalinty
- Calcium
- Magnesium
- Phosphate
- Nitrate
- Nitrite
- Ammonia
- Iodine
- Potassium
- Iron
- Might send in samples to triton on first and last day for more information.

It will take me a week or two (hopefully) to set this up, in the meantime, if you have comments or suggestions feel free to chime in.

[bertoni]

It's not necessary to stir the water, although the pump should be fine to use as long as the temperature doesn't rise.

[StrikerKratos]

Is this because the new saltwater doesn't contain any organics? I've always been recommended to use a small pump on a timer to keep it from going stagnant.

[bertoni]

Yes, organics are the only issue in deciding whether the water will need a pump. I've stored IO for months without a pump, and there was no detectable decay.

[sleepydoc]

This isn't decay, but I've noticed issues with my saltwater 'settling.' After doing a water change, I would refill my 32 gallon water bin with DI water, add the appropriate amount of salt then set the mixing pump to mix for 2 hours and walk away. The next day I came back and checked the salinity and found it to be low (say 1.022) so I'd add another cup or cup and a half of salt and mix the water. When I would come back and check the salinity it would be around 1.030.

At first I thought I had just made a mistake, but after it happened 2 or 3 times I figured something was up since there should be no way for 1.5 c of salt mix to raise the salinity that much. The only thing I could think of was that the water was settling out and the sample I took from the top of the bin was a lower salinity than that at the bottom. Since then I've turned my mixing pump on for 15 min before checking the salinity and never had an issue.

[bertoni]

I don't think that saltwater itself can't "settle" per se. Over time, any calcium carbonate precipitation can settle to the bottom, but that's only because it precipitated. I'm not sure what might have happened in your case, but I'll look around.

[sleepydoc]

Assuming the salt mix was totally dissolved and it was well mixed I wouldn't think so, either. I mixed it for 2 hrs with both a power head and a Fluval SP4 pump, so it should've been well mixed.

I never tried checking the SG, then mixing it and rechecking. I'll have to do that with my next batch.


Sent from my iPhone using Tapatalk

[reefwiser]

Red Sea recommends using their salt right after mixing.

[jdccroad]

It does settle. I have a 165g drum and without circulation for a day the water at the bottom has a higher salinity than the water at the top. This is after thoroughly mixing for an hour with a huge 2500 gph Panworld.

[StrikerKratos]

Originally Posted by reefwiser

Red Sea recommends using their salt right after mixing.

Correct however I am not using Red Sea Coral Pro, I am using regular Red Sea Salt which can be stored.

[reefwiser]

I use the blue bucket and it doesn't like to be over mixed either.


Sent from my iPhone using Tapatalk

[iammrhappy]

I use a Iwaki pump and I mix my 55 gallon barrel about 6 times a day at 30 mins each time.


My salinity is 1.026 everytime I test it. I have a cap with a gasket over it to prevent Evap.


I have a dual head stenner pump that does my water changes everyday. It changes about 2 gallons a day. My DT salinity has stayed the same ever since.

[StrikerKratos]

I just got the OK to grab some brand new, empty gallon jugs from work. I will be mixing a batch of regular Red Sea salt and a batch of Red Sea Coral Pro salt. I will report back with any changes I see over time. I will also test at varying depths, there will be no flow in these jugs after a full mixing.

[atp0726]

Originally Posted by StrikerKratos

I just got the OK to grab some brand new, empty gallon jugs from work. I will be mixing a batch of regular Red Sea salt and a batch of Red Sea Coral Pro salt. I will report back with any changes I see over time. I will also test at varying depths, there will be no flow in these jugs after a full mixing.

I would be curious to know if you get a strange not so pleasant odor after letting the mixed seawater sit.

I use a 32 gallon brute, I mix up my saltwater and let it sit covered in my basement until needed without heat or agitation. I then plug in the heater and pump a few hours before doing a WC. The basement stays roughly between 60-68 degrees year round.

I have used B-ionic salt mix and now Red Sea Pro and I still get the same strange smell after it sits. Not sure what to compare it to but definitely doesn't smell like fresh seawater. Never had a problem using it but have been thinking about adding at least a powerhead if necessary to see if the smell improves.

[Sk8r]

One of the ongoing problems is that saltwater is ideal for bacterial growth, and many containers have surfaces that have habitat. Be very careful about transference on pumps, hoses, etc.

[jason2459]

Originally Posted by jdccroad

It does settle. I have a 165g drum and without circulation for a day the water at the bottom has a higher salinity than the water at the top. This is after thoroughly mixing for an hour with a huge 2500 gph Panworld.

It will not appreciably settle if fully dissolved and mixed. You may be experiencing precipitated elements settling which would not be beneficial to add to your aquarium anyway and falsely show increased salinity levels.


This was tested by Gay-Lussac 1817, 1819. Using 2 meter columns of seawater and testing the tops and bottoms over a 6 to 20 month period. He found no difference. This is due, at least partially, to molecular diffusion.

However, if those columns were left completely undisturbed with 0 temperature variations over several years its possible there could be a detectable yet very small difference from the top and bottom.

According to Pilson if the salinity was initially 35ppt then after several years with no convection(temperature changes) or disturbances the salinity at the bottom would be 35.006 and at top 34.994.

[jason2459]

Originally Posted by atp0726

I would be curious to know if you get a strange not so pleasant odor after letting the mixed seawater sit.

....

Its common to get a musty smell from stored saltwater. That should be fine. If it smells like rotten eggs thats bad.

[bertoni]

The smell might be hydrogen sulfur (a rotten egg or sulfurous odor) or some other sort of decay. If the smell is not particularly strong, the water likely will be fine after a bit of aeration.

[atp0726]

Its definitely not a sulfer smell. Once the water has been heated up to temp, then poured into a bucket, the smell does not seem to be coming from the water, however, I can still smell it in the bucket. I guess the best thing I can compare it to is the smell after leaving wet clothes in a bag for too long. I know gross but that is what comes to mind. Must be some kind of bacterial buildup. It has never seemed to affect livestock. I may rinse out to brute and see if a powerhead or pump solves the smell issue.

[bertoni]

You could treat the bucket with chlorine and rinse it very well. That might reduce the problem for quite a while. If you are using a salt product that contains organics, switching to a different mix might help as well. Salt products with organics are going to have this issue because the organics decay.