Free sand, Few concerns

[Visionist]

I needed some aragonite for my refugium in a 10g sump and my 20g long needs a little extra sand as well. My lfs was out of sand but he said I could have 40lbs of aragonite that a customer left in a tank they sold to the lfs. The sand was wet still, very green and grimey and needed to be rinsed very well. I rinsed it till it ran clear and it doesnt look too bad. The only concern is that there seems to be a fair bit of "tid bits" as in shell fragments etc. Will this cause any issues?

[whiskey2771]

following very interested in this !

[NaturalViolence]

Shell fragsments? No. Metal sulfide, detritus deposits, and hitchhikers are mainly what you need to watch for.

[Visionist]

Shell fragsments? No. Metal sulfide, detritus deposits, and hitchhikers are mainly what you need to watch for.

I rinsed it for about 20 minutes in very hot water, I would think that should kill most things?

[tennis20]

to really make sure you could just boil the sand in water or dry it out in the sun for a few days.

[atrox]

Got a good deal on some sand from a lfs display tank that had sprung a leak and was set up for two years. 20$ for 100lbs. Learn from my mistakes.....rinse the heck out of it.

[NaturalViolence]

to really make sure you could just boil the sand in water or dry it out in the sun for a few days.

 

That would remove hitchhikers but would not remove organics.

 

Rinsing with freshwater not only kills hitchhikers it also pulls out organics as long as you blast the living heck out of it to make sure any detritus gets kicked up into the water column before draining. Stirring while rinsing also helps a lot.

 

I rinsed it for about 20 minutes in very hot water, I would think that should kill most things?

 

Yes. But depending on how you rinsed it the detritus may still be there.

[Tamberav]

+1 Pour boiling water over it!

[JavaJacketOC]

Bake it in the oven on 250 for about 20 min or however long it takes the center of the container you use to get to 250 degrees, that should kill anything in it. Following that you should probably soak it in some RODI water for 24 hours or rinse it extremely well with RODI water,.

[atrox]

I actually cycled my tank with that sand and although it was filthy and die off was on a global scale it made my tank a super nutrient rich stable system as a result. I have crazy amounts of pods, worms, pineapple sponges in the thousands and the random upside down jelly fish show up.

[seabass]

It's calcium based; so in addition to surface organics, the sand could potentially leach phosphate and/or copper (depending on the environment it was in). No amount of cleaning with rinse these off of the sand (or rocks that were in the system). However, it's possible that the sand will not leach phosphate, and it was never exposed to high copper levels. Without knowing the background, you just won't know for sure (without testing).

[Visionist]

 

That would remove hitchhikers but would not remove organics.

 

Rinsing with freshwater not only kills hitchhikers it also pulls out organics as long as you blast the living heck out of it to make sure any detritus gets kicked up into the water column before draining. Stirring while rinsing also helps a lot.

 

 

Yes. But depending on how you rinsed it the detritus may still be there.

Ill rinse it some more and let it soak with peroxide as well.

[NaturalViolence]

It's calcium based; so in addition to surface organics, the sand could potentially leach phosphate and/or copper (depending on the environment it was in). No amount of cleaning with rinse these off of the sand (or rocks that were in the system). However, it's possible that the sand will not leach phosphate, and it was never exposed to high copper levels. Without knowing the background, you just won't know for sure (without testing).

 

But copper can't bond with either calcium or carbonate so how would that happen?

 

As far as phosphate is concerned this is grossly overstated in the hobby. Most of the phosphates leaching from LR and LS come from the breakdown of detritus and dead hitchhikers into organic phosphates. These are easily removed via GFO, algae growth, or curing. In this case he could cure the sand by blasting it with water, stirring it, and then dumping out the waste water. Then just leave it in a tank full of saltwater and stir the sand while doing a water change every day for a few weeks. That would remove any trace of phosphates except some inorganics.

 

As far as those inorganics go they tend to exist in very trace amounts since inorganic phosphates are rapidly absorbed by organisms and don't bond very well to CaCO3 unless the PH is extremely high. Once they are bound they aren't very soluble. For them to be rapidly leeched back into the system the PH would need to be very low. And even if that were the case they would be easily removed via biological absorption and/or GFO. If he's really concerned about it, which imo he shouldn't be, then he could just give it an acid bath after curing.

[seabass]

But copper can't bond with either calcium or carbonate so how would that happen?

So are you saying that live rock (or sand) will not adsorb copper? I've read that live rock will adsorb copper medications (making it a less effective treatment, and making it unsuitable for future inverts).

 

However, I'm not able to address the specific chemistry aspect of your question.

 

As far as phosphate is concerned this is grossly overstated in the hobby. Most of the phosphates leaching from LR and LS come from the breakdown of detritus and dead hitchhikers into organic phosphates.

Likewise, phosphate can precipitate onto the surface of calcium carbonate, such as onto live rock and sand. The absorption of phosphate from seawater onto aragonite is pH dependent, with the maximum binding taking place around pH 8.4 and with less binding at lower and higher pH values. If the calcium carbonate crystal is static (not growing), then this process is reversible, and the aragonite can act as a reservoir for phosphate. This reservoir can make it difficult to completely remove excess phosphate from a tank that has experienced very high phosphate levels, and may permit algae to continue to thrive despite cutting off all external phosphate sources. In such cases, removal of the substrate may even be required.

Source: http://www.advancedaquarist.com/2002/9/chemistry

 

In this case he could cure the sand by blasting it with water, stirring it, and then dumping out the waste water. Then just leave it in a tank full of saltwater and stir the sand while doing a water change every day for a few weeks. That would remove any trace of phosphates except some inorganics.

While effective at removing organics (and the phosphate that it contains), this will not leach out the inorganic phosphate that has been bound to the sand.

 

As far as those inorganics go they tend to exist in very trace amounts since inorganic phosphates are rapidly absorbed by organisms and don't bond very well to CaCO3 unless the PH is extremely high. Once they are bound they aren't very soluble. For them to be rapidly leeched back into the system the PH would need to be very low. And even if that were the case they would be easily removed via biological absorption and/or GFO.

I think this might be fairly typical. However, when exposed to high levels of phosphate, sand and rock will become a phosphate source that you will have to manage. Something that you wouldn't necessarily have to deal with when using new sand.

 

If he's really concerned about it, which imo he shouldn't be, then he could just give it an acid bath after curing.

Again, an effective way to clean rock, but this will not release the phosphate that is already bound to it. I've used muriatic acid in an attempt to remove the phosphate from dry rock that was leaching phosphate. I dissolved about 20% of the rock (by weight) with the acid; however, the rock still leached high amounts of phosphate into the water. Plus, I feel that acid would dissolve too much of the sand (and making the remaining grains much smaller).

 

 

While I agree, that this might not be typical, my warning was for a basically unknown source of used sand.

[NaturalViolence]

So are you saying that live rock (or sand) will not adsorb copper? I've read that live rock will adsorb copper medications (making it a less effective treatment, and making it unsuitable for future inverts).

 

However, I'm not able to address the specific chemistry aspect of your question.

 

 

My bad. It appears copper can bond with carbonate at a high Ph.

 

 

Likewise, phosphate can precipitate onto the surface of calcium carbonate, such as onto live rock and sand. The absorption of phosphate from seawater onto aragonite is pH dependent, with the maximum binding taking place around pH 8.4 and with less binding at lower and higher pH values. If the calcium carbonate crystal is static (not growing), then this process is reversible, and the aragonite can act as a reservoir for phosphate. This reservoir can make it difficult to completely remove excess phosphate from a tank that has experienced very high phosphate levels, and may permit algae to continue to thrive despite cutting off all external phosphate sources. In such cases, removal of the substrate may even be required.

 

 

That doesn't really conflict with the section of my post that you quoted at all.

 

 

While effective at removing organics (and the phosphate that it contains), this will not leach out the inorganic phosphate that has been bound to the sand.

 

 

 

Which I said if you'll just reread the last sentence you quoted in this section.

 

 

I think this might be fairly typical. However, when exposed to high levels of phosphate, sand and rock will become a phosphate source that you will have to manage. Something that you wouldn't necessarily have to deal with when using new sand.

 

 

While I agree, that this might not be typical, my warning was for a basically unknown source of used sand.

 

 

I agree. But the chances of this happening in ordinary circumstances are next to none. The risk of phosphate leaching from thoroughly cured rock is grossly overstated in this hobby. There is little reason to fear it.

 

 

Again, an effective way to clean rock, but this will not release the phosphate that is already bound to it. I've used muriatic acid in an attempt to remove the phosphate from dry rock that was leaching phosphate. I dissolved about 20% of the rock (by weight) with the acid; however, the rock still leached high amounts of phosphate into the water.

 

 

That's very unusual in my experience.

 

 

Plus, I feel that acid would dissolve too much of the sand (and making the remaining grains much smaller).

 

 

This is a legitimate concern.

[seabass]

"... then this process is reversible, and the aragonite can act as a reservoir for phosphate. This reservoir can make it difficult to completely remove excess phosphate from a tank that has experienced very high phosphate levels, and may permit algae to continue to thrive despite cutting off all external phosphate sources. In such cases, removal of the substrate may even be required."

 

That doesn't really conflict with the section of my post that you quoted at all.

It doesn't. However, it's in agreement with the concern that I originally expressed - that if the sand came from a high phosphate environment, it could continue to leach phosphate (even if it were free of organic material).

Many people quit the hobby because they are having problems. A common problem that people have is algae (due to high phosphate). They can't seem to get rid of the algae and quit the hobby. Enter used sand and rocks that may or may not be leaching phosphate. I just pointed it out because the thread was about concern over this sand.

We are in agreement, except for our opinions on the probability. While I don't believe that it's highly probable, I still feel that it's a valid concern. Good discussion though.

 

 

And while I think exposure to high levels of copper is highly unlikely, the consequences would be much worse.