Aragonite sand turning to sandstone

[reefpour]

My tank has been set up for 5 years. I noticed the other day that a large clump of my aragonite sand had turned into a lump of sandstone. Further investigation turned up many more lumps. I made aragocrete tables (ala GARF) to place my live rock on, and under the tables (they have three legs approx 2" long) was pretty much all sandstone.

I obviously have not had enough sand sifters/stirrers at work.

Anyone else had this happen to them? Any thoughts on what I should do?

BTW, this is a shallow sand bed, approx 2 1/2" deep.

Thanks,

 

[Vincerama2]

Are you dosing kalkwasser? I heard that sometimes an alkalinity problem can lead to clumping aragonite.

V

 

[reefpour]

I don't use kalkwasser. I have a calcium reactor. pH is 8.2 mornings, and 8.3 when lights go out. Alk runs 9 DKH and calcium is at 440.

Now I might add that in 5 years, my parameters have gone a bit wiggy a time or 2. When I got the calcium reactor, I quit testing for calcium and alk after 3 or 4 months (everything seemed to be great with no maint needed). Then when my favorite large acro RTN'd on me, I found I had a clogged discharge line, and my calcium was in the 250 range...

I guess the clumps could have formed a while ago. I don't pay much attention to my sand bed. I know, I probably should...

 

[PatrickJ]

more flow to your sand?

 

[reefpour]

Good thought PartickJ. Do you mean enough flow that the sand is moving around? Or just a good flow over the top? Of course, I don't get much flow under my "table" base rocks...

 

[Vincerama2]

Maybe add some critters that move the sand around too. Nassarius snails? Some of those sand-filtering fish?

V

 

[Gary Majchrzak]

Critters and water flow aren't the problem. Low pH and/or supersaturation of ca and alk caused sand particles to fuse.

 

[cwegescheide]

same thing happened to me after ALK was high for too long. My "sand bed" is now a rock bed.. I dread the thought of chipping it outa there... Atleast no detrius will build up in there