[bpaul_jpaul]

Hello. I have great water movement in my 65-gallon reef tank. But I keep finding that my sand bed that is about three inches deep keeps clumping up. It almost turns rock hard. I keep the calcium at 400 to 450 and the dKH around 10 to 12. I have a ton of snails and some worms mostly in the live rocks. The sand grade is fine to about 2 mm size. Mostly fine sand is used.

What gives and how do I keep it from clumping?

Thanks
Brandon

[oscar c]

hermit crabs might help.about one per gal.

[kevinpo]

When the water is near saturation of calcium and buffer you stand the possibility of some drop out or plate out. Small crystals form on the grains of sand bonding them together to form an almost cement-like rock. Let your calcium level drop to about 370-390ppm and your KH down to 9-10 dKH. This should fix the problem. IME these levels are much easier to maintain without a seasaw effect and growth rate of corals remains the same. Natural Sea Water runs about 400 ppm calcium and 8dKH of KH.

HTH,
Kevin

[bpaul_jpaul]

Thanks

I will give this a try

Brandon

[Ninong]

Brandon,

It is possible that mineral precipitation could be responsible for some of your sand clumping problems but in most cases the problem is caused by a lack of sandbed infauna. The sandbed infauna turn over the sandbed grains constantly to prevent cohesion and clumping. Also, the infauna prey on bacteria that secrete substances that can cause the sand grains to become coated with a biological film that acts like a glue binding the grains together. Without sufficient sandbed infauna to keep the bacterial population in check, clumping can result.

I would suggest that you remove any clumps from the tank and replace with fresh sand. You should add some new sandbed "critters" to your tank to refresh your sandbed infauna. These detritivores are available at several online vendors now. Two vendors that come to mind are: www.ipsf.com and www.inlandaquatics.com but there are others.

You should be aware that ornamental shrimp and hermit crabs are predators on the 'good' worms and other critters that you need for your sandbed; therefore, you should want to take that into consideration when stocking your tank with such creatures. That means don't go overboard with hermit crabs and shrimp. A large population of hermit crabs would be detrimental to your sandbed infauna.

[VIC]

Ninong,
Question, I have a 2 inch sand bed that I am in the process of increasing to 6-7 inches (about 1/4-1/2 inch per week) My sand population is mostly worms. In your opinion, should I get a sand kit and add it at this point? I only added about 1/2 inch to date and I am concerned that I will not have enough creatures to keep the bed moving and it will brick. I keep the dkh at 13 and the calcium between 375 and 390. So far no bricking but adding 5 inches is alot eventhough it will take me several months to do so. Putting the cost of these kits aside, would it be smart to put down a dose of critters, wait a week or two and then continue with the process?
I have about 2.5 inches of bed now with a few hermits and snails also 3 or 4 stars. Nothing else to stir it up. What creatures would you suggest? (maybe a cuke or a gobie. )The tank is 155 gallons
Thanks for your help. Also how many hermits woold you suggest for this tank with a 5-7 inch dsb.
VIC

[Ninong]

Originally posted by VIC:

Question, I have a 2 inch sand bed that I am in the process of increasing to 6-7 inches (about 1/4-1/2 inch per week) My sand population is mostly worms. In your opinion, should I get a sand kit and add it at this point?

Yes, I think it would be a good investment. You want as much diversity as possible to increase the stability of the total population.

I only added about 1/2 inch to date and I am concerned that I will not have enough creatures to keep the bed moving and it will brick. I keep the dkh at 13 and the calcium between 375 and 390.

The population of sandbed infauna will multiply on its own to take advantage of available habitat provided you have a healthy diverse population to begin with but adding some more just enhances your chances of success. A dKH of 13 is fine; anything much higher might introduce complications in balancing your chemistry. I kinda like the number 12 dKH. I think you should shoot for a little bit higher calcium. I believe 425-450 would be better than 375-390.

So far no bricking but adding 5 inches is alot eventhough it will take me several months to do so.

Increasing the depth of the sandbed does not increase the potential for sandbed problems. As long as the sandbed contains a healthy population of infauna it will be OK whether it is 4" deep or 8" deep, or anything in between.

Putting the cost of these kits aside, would it be smart to put down a dose of critters, wait a week or two and then continue with the process?

Yes, I think so.

I have about 2.5 inches of bed now with a few hermits and snails also 3 or 4 stars.

What kinds of stars do you have? You want to avoid the white sand shifting starfish (Archaster typicus) because it will devastate the population of upper layer sandbed infauna, throwing the total sandbed infaunal relationships out of whack. I would suggest you increase your snail population for that size tank.

Nothing else to stir it up. What creatures would you suggest? (maybe a cuke or a gobie. )The tank is 155 gallons

A couple of the sand processing cukes would be a good addition for your tank. You want to avoid any sand sifting fish, like certain gobies, that are sifting the sand to eat the sandbed critters. I would suggest you get a few dozen of those little Nassarius spp. snails. They are carrion eaters and they burrow in the upper layer of sand, which stirs it up a bit and they do not prey on the sandbed infauna.

Thanks for your help. Also how many hermits woold you suggest for this tank with a 5-7 inch dsb.

I kinda like hermits so I am not against having a few in any size tank. I just don't believe a large population of hermits is beneficial overall because of the other consequences. I think snails are better for most algae. How many hermits you put in a 155-gal tank is a personal preference. I just don't agree with the online vendors that recommend a certain number of hermits per gallon. So you might want to consider as little as 10 hermits or as many as 20 for that size tank. Or you could consider none. Some people advocate a lot larger number than that for hermits but I think it is wiser to hold down the hermit population myself.