How do you prevent your sand from 'caking' or solidifying?

[Matt Rogers]

How do you prevent your sand from 'caking' or solidifying?

I had this problem from time to time.

What causes it?
Water quality?
Lack of detrivores?

[Jason McKenzie]

Is it not usually a chemical imbalance between CA and ALK? I could be wrong

J

[geekdafied]

The only thing I found to prevent that is by siphoning it out from time to time. Over time, detritus and various organics produce acids when they deteriorate. The acids cause the sand particles to clump/solidify making your sandbed usless. This is why you dont use a DSB. Though this can happen even if you have a 2" sandbed except you didnt waste a lot of money buying more sand that clumps on you. Also a larger grain size such as .8-1.5mm size sand is less likely to solidify on you.

[morejongg]

occasional stirring and Nassarius snails

morejongg

[amcarrig]

I have to say that I have never had this problem. I'm sure that I've read what causes it but my mind is shot to heck at the moment and I can't remember what I've read

[Camilsky]

Hey Matt!
Sand grains form very adsorbent layer that attracts and captures lots of organic matter. This adsorption surface is used by many favourable micro-organisms as an interface at which they can catalytically degrade proteins, lipids, nucleic acids. The importance and the properties of substrate layers were studied for many years. It has been even suggested they might have been crucial in the evolution of life on earth (so called auto catalysis theory of biochemical evolution). You can read more about this fascinating hypothesis over here. Moreover, degradation products (very often organic acids (eg. amino acids) form insoluble salts with an excess of floating mineral metals like Mg,Ca, or Ba. Once a tiny insoluble salt crystal is formed on the surface of sand grains it serves as a scaffold for the growth of other salts (this tiny crystals that initiate the growth of a bigger one are called the nuclei of crystallization), accelerating the binding of surrounding sand grains. Therefore, you end up with a fancy crystalline like phase that contains marine-water elements bound with silica grains. I can imagine this kind of problem is rather difficult to avoid due to great complexity of microbiological flora and fauna of a typical sand bed. However, strict control of water parameters (especially the metal ions that easily form insoluble salts: Mg, Ca, and Ba) + keeping stable pH/alkanity should decrease the chance of finding funny looking solidified sand bed I would also follow geek's advice concerning siphoning detritus from the surface of the sand bed!

Cheers!

[lunatik_69]

Hey Camilsky, I can appreciate a smart person, but I didnt understand a damn thing that you said!

[wastemanagement]

Well im not such a technical as camilsky (bless her heart ) but my 2 six spot gobbies seem to a pritty good job of turning over my sand and keeping it free of any caking.

[Reefdiver72]

You get a maroon clown pissed off after you move her anenome and she will redecorate the sand the rock the corals and everything now shes trying to move a korlia. she does hit them and move them pretty good.I now have a bare bottom all the sand is up in my live rock and inn the back of the tank.

[amcarrig]

Originally Posted by lunatik_69

Hey Camilsky, I can appreciate a smart person, but I didnt understand a damn thing that you said!

+1