RDSB-5 gal Bucket...

[Gravesj1s]

Hmmmmm, well, actually NO3 reducing microbes are not anaerobic.They are aerobic (oxygen loving).

Aerobic bacteria will reduce Nitrate when little to no oxygen is is available,they will then consume the oxygen atom from NO3 leaving free nitrogen.So it is incorrect to say anaerobic bacteria are responsable for this.
-Graves

 

[aaron1987]

If you bury a large piece of LR with tons of organic material on it - you're going to have an issue. Bury a piece with minimal life and I can't see how it could possibly be an issue. A buried chunk of ruck is not inherently going to cause nitrate issues; the only way it would cause a nitrate issue is if something is decaying on it or becomes trapped on it -- Neither of which is likely on a rock that's buried and only alive with bacteria.

 

[Gravesj1s]

questionable rdsb effects

questionable rdsb effects

I think some would be surprised to know that most denritrification is most likely occuring in the upper1-3 centimeters.

Study done in 1984 by T.K Anderson found 70-90% of overall dentrification was located in the uppermost centimeter. The remainder 10-30% was found at 1-3 centimeters.-B.J Finlal.1995

I see absolutely no reason to have or conclude a deep sand bed does anything constructive to a reeftank.
I think this should add some conversation.
-Graves

 

[jman77]

Gravesj1s,

I agree , look at the sand in your tank and where you see bubbles forming. The bubbles do not start 4 inches below the surface of the sand , you usually see it withing the inch or so.

I think the DSP theory caught on the way it did was due to 2 fold ...

1) one the need for a deep sand bed due to the fact that the upper layers get disturbed by the animals in the tank

2) In the attempt to mimic the Plenum systems that used the DSB for filtration and calcium addition .

 

[Gravesj1s]

-Jman77,

I think your obsevation is interesting.I too, notice where the bubbles seem to start to rise when looking at the front of the tank at the sand layer.I also notice that the bubbles seem to start where cyanobacteria is growing. I guess it could be cyano or microbes processing NO3 and the bubbles we are seeing are free (N).Maybe combination of them both.

Its possible that a deep sand bed could be malfunctioned by being disturbed but I'm not convinced.I acually vacum the sand layer in my tank.I have never had any issues.I feel the "gunk" I get out is a more positive attributor than detrimental effect.I started doing that because a sandbed of anytype is not going to do anything for po4. Unless you grow algae you have no way of exporting this element and its potential accumulation.

Lastly, yeah again I agree with you on the dsb trying to mimic the plenum system. Only thing is the sand doesn't really disolve at any rate worth noting,secondly , the plenum was a knock off of the Jaubert system in Monaco whitch never operated the way hobbists were told. Those systems were all "open" meaning they had to some degree water exchanged with the ocean.that is maintaining Ca++ and carbonates.Not through the disolution process that was initialy reported by some of these authors &experts.
Anyway, these are just my thoughts that I felt were worth mentioning. I dont care much for getting into huge debates these days but I have a closet full of crap I ve purchased over the past 22 years listening to some of the experts out their.
-Graves