Do phosphates bind to sand?

BtheReef

New member
I started a thread in the discussion forum asking how to go about cleaning old sand to reuse. Here's the link to the thread
http://reefcentral.com/forums/showthread.php?s=&threadid=786576

A question came up that would probably be better answered by you. If I were to hose the sand removing all detritus and allowed it to sun dry, would this sufficiently clean the sand to use in a new system? Is phosphate leaching a problem if there is no detritus or organic waste left? Can undesirable elements bind to the sand itself and then diffuse into the new system?

I guess that was more than one question :)

Thanks for any help.
 
Phosphate can bind directly to the sand, and removing it is not going to happen by simple hosing. Organic detritus loose in the sand will be washed away. The sand may also have attached metals (e.g., copper) and other undesirable impurities.

When I recently took down a 10 year old tank and set it back up in a slightly larger tank, I tossed out the sand and started with new sand because of these issues. :)

I discuss phosphate binding to CaCO3 in this article:

Phosphorus: Algaeââ"šÂ¬Ã¢"žÂ¢s Best Friend
http://www.advancedaquarist.com/issues/sept2002/chem.htm
 
Ok, so simple washing and drying won't do. What about my original idea of cooking the sand similar to cooking rock. In the original thread I suggested keeping the sand in a rubbermaid container of saltwater and cleaning it every week or so for several months.

I don't know what your personal thoughts on cooking rock are, but there seems to be at least some validity to it. If only to rid extremely old rock of internal detritus and external algae. What about adding a phosban reactor to the tub while the sand is cooking?

This may seem like a lot of work, but I really want to use the sand I have if possible. There aren't too many viable options locally and I'll have plenty of downtime before I set up the new system.

THanks for the respected advice.
 
Yep, I thought about compaction being a factor. Seems like my options are becoming singular, get new sand. Guess I'll start searching for the 'alternate sand' threads.

Thanks,
 
Well, Ive had it since I set my tank up (almost 9 yrs) and it includes several different grain sizes and types, shells, etc.. There's also sand from several other tanks I've had or friends had. It just has character and a very natural look.

I agree it seems funny to try to save a sand bed, but I'll have a lot of time before I re-set up the tank and just wanted to experiment a bit.

Thanks for your help.
 
Hi Randy: Not to highjack this thread but I have a question(s)?

I am planning to overhaul my 155gal tank that has been up & running for 6 years now. I noticed that you mentioned that Cu can bind to the sand substrate. When I initially set up the tank, and being a novice at best, I had an outbreak of ICK & had to treat the main tank with Cu which I know is a no no. However, after the outbreak cleared I used plenty of Cu removal media. I know that it's hard to test for Cu but the kit that I had at that time (? name) showed no discernible reading for Cu. Anyway, since that time I have been able to keep fish with no problems including a Mandarin that has been alive & happy for 3+ yrs. The problem is that I have never been able to keep any Acropora's, Euphyllia's, clams, or SPS corals alive with any success. Is it possible that it's due to the leaching of Cu after all of this time?

To be honest, I also have had problems with elevated NO3 & PO4. I have recently installed a 30 gal refugium (2 months ago) which I hope will help in this regard. I know that I am asking you for answers which admittedly would be difficult without knowing much more about my system. However, I was mainly interested in the possibility of Cu leakage from the substrate.

Also, do you think that I should replace the old sand bed with new sand? I am planning on replacing much of the LR much of which was also in there when I did the Cu treatment.

Thanks for your time & expertise!

Best,

Steve
 
Is it possible that it's due to the leaching of Cu after all of this time?

Yes, that is possible. Can you keep things like snails or hermit crabs?

Also, do you think that I should replace the old sand bed with new sand? I am planning on replacing much of the LR much of which was also in there when I did the Cu treatment.

I would consider that.

Was there live rock that was also exposed?
 
Yes, I can keep hermits & snails. Also a yes to the LR being exposed as well.

Thanks again,

Steve

BTW, where is Arlington in relation to Lawrence MA? The reason that I am asking is that I am going to be in that area on April 6th & again on the 26th & was wondering about getting together if possible?
 
I do not know how sensitive corals are relative to snails, but msot folks that find they have copper problems find it kills snails, so perhaps that isn't it.

where is Arlington in relation to Lawrence MA?

Arlington is just outside of Boston, while Lawrence is near the NH border. :)
 
Thanks again!

If I find that I will or can make more time during those excursions I will PM you & perhaps I can drop by? BTW, any chance that you will be at the NERAC convention taking place on LI next weekend 3/11?

Steve
 
This is an old thread, but Ill ask any how. Randy, in the first part you said, you tossed out the sand when you set up again. But then later, you say that if you have a good PO4 export system it should be fine. I just started to cycle two days ago and my first tests show .65 ppm PO4. I am fairly certain its from used sand that I cleaned. Should I just start over with new sand or can the export system really solve it. I will run gfo and refugium.
 
It can leach out of rock or sand. Hard to tell until it does it. Mine waited a year to start handing me phosphate. GFO is adequate, but you have to use a lot (it saturates) and you have to be patient.
 
I'd probably ditch the sand once I was sure it was the source, but over time, GFO can lower the level. It can take a lot of GFO, though, which can be costly. The refugium can help, too, but you'll have to prune the macro algae regularly. Lanthanum phosphate is an inexpensive alternative, but it forms a precipitate that should be removed.

I'm not sure yet that the sand is the source, though. I might give the tank some time, but I don't know what's in it, so I can't judge very well.
 
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