Sand cleaning.

[Jnicho]

I've done it both ways...after seeing what gets siphoned out every few weeks, there is no way you can convince me it's "better" to leave that stuff in there...critters can break it down to a point, but poop is still poop even it's it's in smaller pieces, LOL! It just doesn't get broken down fast enough to enter the water column and get filtered/skimmed out IMO...I can't speak at the microscopic level, but visually my regular sand cleanings have little impact on the level of benthic lifeforms in my sand bed.

[Elegance Coral]

Originally Posted by Neuticle

A bad idea? I have a 3" sand bed full of critters and I've never had detectable nitrates.

Thanks to a few articles and at least one book that I know of, people have gotten the wrong idea about what critters in a sand bed do. They do not remove harmful substances like nitrate and phosphate. They help to release these substances into the environment. Not remove it.

If your sand bed is "full of critters", it must be full of food for them to survive on. These critters feed on detritus (rotting organic matter). As long as a solid particle of detritus remains intact, the nutrients it holds can not effect the system. Those nutrients like nitrate and phosphate don't get released from the particle until critters begin to break it down. So......... In a sand bed "full of critters" and detritus, there will be a constant release of nutrients. Like nitrate and phosphate.

The effects of such a sand bed on a system depends on many factors. The size of the sand bed in relation to the total water volume, the amount of algae growing in the system, temperature, the amount of detritus in the sand, the number of critters feeding on it...................
There are many reasons you may get undetectable readings of nitrate in a system with a sand bed as you describe. That's not proof that the sand bed is reducing nitrate, or that your system is free of nitrate.