Solidification of Arragonite Substrate

[riemannp]

Hello,

Like many, I occasionally fall behind with my reef water chemistry--including lapses in my manual 2-part dosing. I notice solid blocks of my substrate occur from time to time, including some pcs 4-6" long. I'd be grateful for an explanation as to what causes this. I know what the solution is: i.e. just stay on top of my water quality. Regardless, any feedback is greatly appreciated.

 

[user 26995]

I am not really sure why it happens either. I was told many years ago when I bought the sand, that it will do that. I have not actually seen it happen though. unless it has to do with excrement from inverts, worms in the substrate that bond with the sand to make it solid. I dont really know, but thats my guess.

 

[mfinn]

I remember this from my deep sand bed days.
Calcium in the water was binding to the aragonite sand causing it to clump, (sometimes large clumps)
Some said it was as hard as concrete.

 

[user 26995]

Well that makes sense. I knew someone would have an answer.

 

[riemannp]

Thanks. Indeed, some of the clumps I have encountered are quite hard, and tough to break

 

[riemannp]

***Has anybody had their pumps start to freeze up do to calcium carbonate buildup?***

This "solidification" also increased a "caked" layer on my pumps, etc. In fact, my large skimmer stopped working property, until I soaked it with vinegar. I've maintained a reef aquarium for over 10 years, but can't recall such a strong case of calcium carbonate buildup--including the solidification in the substrate.