What causes clumping sand?

[tmz]

Thanks for the write up Boomer. Is the "activity" referred to in #1 which lowers the local ph bacterial ie enzymes,acids etc?

In my case the clumping in the old sand is a mix of very hard clumps and some you can crush in your hand. All are at least an inch or two below the surface of the sand where it is likely less flow would allow for localized ph drops.Probably a little #1 and a little #4.Alk is around 9.5dkh and vodka vinegar is dosed.So bacterial activity is likely and th dkh isn't very high.

 

[Boomer]

Tom, yes that is correct on activity, Meaning, anything that lowers the pH causing dissolution.

 

[vitodog]

I had the same problem with my sand bed recently and all of my parameters i.e., Alk., Ca and Mg fell within the acceptable ranges. I'm sure the problem lies somewhere in all that is mentioned above. However, when I posted this same question, someone suggested purchasing a Goby (I purchased a Diamond Goby) and a cuc that consisted of some sand sifters, such as Nassarius Snails. Well, the goby went right to work and 2 days after placing these animals into my tank, my sand looks like I just placed it in the tank (snow white) and no signs of clumping. I hope it stays this way. This method was the solution in my case. It might work for you as well. Good luck.

 

[Boomer]

Yes, I agree. Bioturbation is a big key and so is flow rate over the sand.