substrate

[C-Dog]

hey guys i was jsut wondering the advantages and disadvantages of having:

-bare bottom
-aragonite
-crushed coral
-aragonite/crushed coral

thanks guys,
Corey

[beowulf]

From the marinescape presentation it would seem having a nice 3-4 inch layer allows for a lot of good bacteria to help keep that tank healthy.

[sniggir]

Bare Bottom is good aswell but it all depends on what you want to do alot of people who run BB tanks do this because they are keeping sps.. talk to xnon..and CN they both run BB tanks and are very happy with they the big diference is flow you need a lot more flow woth BB tanks

[shaka zulu]

I have a 90 Gal I am setting up. The footprint is 48" x 24" (I think). How do I calculate how many lbs. of Aragonite to buy if I am looking at a 2" - 3" bed?

[BigDaddy]

A 90 gallon tank is 48 x 18 x 24

Your footprint is 48 x 18.  To get a 3 inch bed of sand, you'd need to buy 150lbs - 5 bags.

Here's the calculator http://www.plantedtank.net/substratecalculator.html

Now, I used silica sand... but since aragonite is around the same size and shape it should be a good rough estimate.  Only thing is a 12 inch square one inch section of silica sand probably weighs less than a 12 inch square 1 inch bed of aragonite.  Not sure if that will impact how many bags you need or not.

[BigDaddy]

As for your question cory, someone has already talked about BB tanks... so I'll talk about DSBs

DSB stands for Deep Sand Bed.  The primary pro of a DSB is increased denitrification (note that Live Rock usually has anaerobic sections where denitrification can occur).  However, there is debate about how effective it is without the use of a plenum.

The primary con of a DSB is that if you don't have a lot of critters stirring up the sand bed, you are going to get a lot of detritus building up in the sand and the potential for large pockets toxic gas which could be released and cause major problems.

Very simple pro vs. con but pretty much it in a nutshell

[sniggir]

for SW tanks you should stay away from silca based sands as they can cuase problems later on down the road.. but bomix white and you can use sands that come from lime stone if you are looking for a cheaper sustatute for argonite or crushed coral.

[Alchemist]

Just by accident I have half of my tank as crushed coral and then there's a sandy playground for other critters too....I think it looks quite natural and means that I can have sand sifting animals and corals that prefer sandy beds and also things like my pistol shrimp that love digging in the crushed coral.  I regularly stir up some of the substrate and occasionally vacuum it too.  I notice a good feeding response when I stir up the bottom from the critters in the tank so I guess it's free food.

[porcupinepuffer]

 I have a 120 gallon tank that's 48x24 with dual overflows, minus the small amount of space taken by liverock, I only needed 3 bags to get a good 3" DSB of reefgrade aragonite.... I believe they were 40 lbs bags each. I've read that a DSB is fine, but years later it can become troublesome with pockets of toxic gas in stagnant areas, but aslong as you have livestock that will stir up the sand bed, it should be just fine. I've also never had a detectable level of nitrate so far.

[ryancarman.com]

i use a combination of aragonite and crushed coral about (20-30 lbs of sand) and about ... 3-4 cups of crushed coral mixed in, in a 29 (30x12x18)

and i have a couple of conchs that cruise around in the substrate and keep it turned up

i find a good combination, however rinse the crushed coral well before setting up the tank and you will save yourself a fair bit of cloudiness from the get go

[kennyman]

I use a 3"-4" dsb of aragonite. According to many sources Aragonite is superior to crushed coral at buffering the PH as it begins to release carbonate at a higher ph.

I chose to go dsb because I wanted the extra denitrification. I got 20 lbs of experienced substrate off a very nice ovas member and it seeded my tank with some awesome benthic microfauna. I also keep Nassarius snails which burrow in the subsrate munching up any organics they can find.

I have never had measurable nitrate or needed to adjust my ph in two years. (knock on wood)

[speckledmind]

For any calculation of reef, go directly to http://www.reefcentral.com

Go down the left hand side where it says " Main Menu " to " Calculators ", all the tools are there.
Here is the direct link just in case http://www.reefcentral.com/calc/SandBed.php

Bomix is a great alternative and real cheap, if you can find some 
The Bomix company no longer makes the aragonite sand, the process was sold to a different company, and I bet it's a aquarium related product company of some sort.

[C-Dog]

kool thanks guys,

i will prob go with a DSB but i was wondering about the good livestock that will stir it up??

lemme know
thanks

[sniggir]

cerith snails, fighting conch, pistol shrimp, sand sifting star fish.... are a few