Need sand clumping reference

[Ping]

I have a small clump of sand slowly growing. It is next to a clam. This is the only place this clumping acures. My water paramiters are good. I do drip Kalk twice a week at night.

I have been unable to locate info on this. I remember reading about placing a clump in viniger, but I dont know what the results mean.

Do clams exude a clumping subsance? Or something else. Any info or cite would be appreciated. Thanks Peter.

[Thunderkat]

What is in the clump that is making it stick?

[GaryP]

That often happens when calcium and alkalinity are high. Having a higher pH can also aggravate this as calcium carbonate has a lower solubility at higher pH. Using Kalk would certain cause you to be at a higher pH then someone that doesn't. That's not to say that your pH is too high. In addition, bacterial action in the sand bed can also catalyze precipitation. I have a feeling that its proximity to the calm is just a coincidence.

Clams do produce threads that they use to attach to the substrate they are sitting on. It could be that the clam was attached to this clump at one time. I sit my clams inside a PVC union that is buried in the sand and let them attach to that.

[Ping]

Thanks Gary, that freshens my memory quit a bit. Which reason above will break up in vinegar.

[GaryP]

Basically vinegar will dissolve the entire clump. Its all dissoved by acid. That is, both the sand and the precipitated calcium carbonate. I don't know if it will work on the byssal threads from a clam. I kinda doubt it. I would just try breaking it up with your hands or by smashing it with a hammer.

I salvaged a tank once where the sand bed come out in one big slab because of overdosing with 2 part. I was able to reuse some of the sand by breaking it up.

[Ping]

I am not attempting to save the sand. Just trying to find and eliminate the cause. I thought I read somewhere that if it is from one of the reasons you mentioned it will need to be crushed with a hammer, eg. the vinegar does not cause it to disolve.

[GaryP]

The byssal threads are made of collagen. That is, the same thing that your nose and ear lobes are made of.

OK, gotcha now. You are just trying to come up with a diagnostic test to determine whether the cause is the clam or not. If you soak the clump in an acid like viengar, it should completely dissolve until all that is left is fine silt. If the clump is from byssal threads, the clump will still dissolve, but will only leave a clump of "goo" that is the leftovers of the byssal threads. IN both cases, this is based on the assumption that you use enough vinegar to completely dissolve the clump. Vinegar only contains 5% acetic acid. Its not a very strong acid and a large clump would neutralize it fairly quickly.

[Ping]

Update; My clam have turned and moved approx 3 inches in the past couple weeks. It is in the sand bed, not on a rock. Hmmm, dont know if this is relative to the sand clumping or not. Any one else have one move?

[GaryP]

Mine moved all the time until I set them into PVC unions. Now they may slump over a little, occasionally, but for the most part they stay where I put them.

[Ping]

Thanks, I may do that.

[GaryP]

Just get some PVC unions a little larger then the clam and bury them in your sand. The clams like something a little firmer then sand to attach to. Many attach to rock. The union gives them something to nestle into and helps keep them upright.