Our mission

Question for collective mind - sand clumping

Vhuang168

Vhuang168

Guest
BARcard
I'm having issues with sand clumping.

Alk is in the 9s, Ca in the 450s and Mg was as high as 1600 as some point but is now in the 1500s.
Levels have been checked by other methods and all the values fall into range.

So I'm kinda stumped. Most of the clumping is along the rock work. The areas free of rock are pretty loose.

Any ideas?
 
Last time @Blaise006 had this issue, it was due to localized ph differences in the tank which led to precipitation in the sand. I believe he was trying to crank the ph up as high as possible and was getting precipitation near where the skimmer was drawing fresh air in due to a localized ph spike. My guess is a similar phenomena and the sand near the rock work has less flow giving the precipitation a better chance to take hold.
 
Having Mg that high should have prevented that.

Days when I'm here, ph is between 8.1 and 8.3. When I'm gone, its from 8.2 - 8.4.

I'm going to start breaking those clumps up and get more sand movers.
 
It could be biological, like a bacterial film causing the clumping. I’ve seen it before but I don’t have any specific recommendations how to prevent it.
 
My sand bed was like concrete in spots when I overhauled my system.
I had to hammer it out with an aluminum pipe. Glad I did not have a glass tank.

The front, with high flow and low detritus, was fine.
The back corners, with low flow, and lots of detritus, were bad.
But really bad was one area in the back where I had rock-work glued together with cement.
Interestingly, that cement was disintegrating, and the rock came apart easier than the sand bed.
(That was before I switched to using epoxy to connect rocks)

So it seems flow/detritus/cement related. But no idea on exact process.
Some of that implies biologicial. Some implies PH.
 
I had that happen to me several years/tanks ago. What I ultimately found out was it was overdosing alk with my 2-part dosing. I don't know for sure what initially triggered it (possibly high pH as alluded to above) but once the clumping started my alk uptake increased right along with it. And so would my dosing. I ran my alk upwards of 10 at that time also. It took me a while to figure out what was happening and I ended up with a good third of my sand bed clumped up. Much of it was at the base of the rocks in the sand. Randy Holmes-Farley over on R2R talks about it and offers up a couple of methods to deal with it. I believe it's along the lines of cutting out your alk dosing for a certain amount of time, a week or so maybe, and switching from soda ash to baking soda for a while. That's assuming you're dosing 2-part and using soda ash. Best to head over there and get the real scoop direct from the source though.
 
rygh said:
My sand bed was like concrete in spots when I overhauled my system.
I had to hammer it out with an aluminum pipe. Glad I did not have a glass tank.

The front, with high flow and low detritus, was fine.
The back corners, with low flow, and lots of detritus, were bad.
But really bad was one area in the back where I had rock-work glued together with cement.
Interestingly, that cement was disintegrating, and the rock came apart easier than the sand bed.
(That was before I switched to using epoxy to connect rocks)

So it seems flow/detritus/cement related. But no idea on exact process.
Some of that implies biologicial. Some implies PH.
Click to expand...
This was similar to my experience.

I’ve stopped running ph from 8 to 8.3. Instead I run the skimmer to keep my PH swing under 1. So now the skimmer cuts off at 8.22 and keep the low near 8.14.

I am still early into this switch, but I choose it since I’m dosing all for reef and it is impossible to combat Alk swings with all for reef and ph swings in my tank. What I have noticed is that my average PH is not significantly different between the two approaches and alk is more stable. I think long term this is a better approach for me.

I may switch to 2 part again to see if I can get a better average PH but keep the swing as small as possible without it being intrusive to my daily tank work.
 
Piper said:
I had that happen to me several years/tanks ago. What I ultimately found out was it was overdosing alk with my 2-part dosing. I don't know for sure what initially triggered it (possibly high pH as alluded to above) but once the clumping started my alk uptake increased right along with it. And so would my dosing. I ran my alk upwards of 10 at that time also. It took me a while to figure out what was happening and I ended up with a good third of my sand bed clumped up. Much of it was at the base of the rocks in the sand. Randy Holmes-Farley over on R2R talks about it and offers up a couple of methods to deal with it. I believe it's along the lines of cutting out your alk dosing for a certain amount of time, a week or so maybe, and switching from soda ash to baking soda for a while. That's assuming you're dosing 2-part and using soda ash. Best to head over there and get the real scoop direct from the source though.
Click to expand...
@Vhuang168, you’re still running a CaRx though right?

JVU said:
It could be biological, like a bacterial film causing the clumping. I’ve seen it before but I don’t have any specific recommendations how to prevent it.
Click to expand...
This was my first thought as well. I’ve never had this experience though.
 
You must log in or register to reply here.
Back
Top