Best Substrate for Fahaka?

[Fat Homer]

Personally, I wouldn't use fine sand for a 4" bed. You're just asking for either problems with anaerobic pockets of toxic gass or a real PITA job of stirring that deep send bed thoroughly (under all decor) every week.

I actually do agree with pufferpunk on this, since i do have a very fine sand base thats about 2.5 - 3inches deep, although at the same time, if you don't mind doing it then its not too big a problem...

 

[RobD23]

why are so many converting to black sand for the salt tanks if it creates such a problem? some people are just a bit paranoid in this hobby i think. (toxic gas!)

 

[Pufferpunk]

Maybe you've never seen the gas bubbles in the DSB of a marine tank? It always stresses not to disturb them & especially do not add sand-sifting creatures to a DSB, because toxic hydrogen sulfide gas will be released into the tank. Fortunately, marine live sand comes with tiny worms. copepods, etc. which will slowly stir the sand, to keep it healthy without disturbing it enough to harm the tank:
http://www.ronshimek.com/deep_sand_beds.html

Hydrogen sulfide will indeed be formed in the lowermost layers of a deep sand bed. It will NOT migrate up through the sediments to poison a tank. Hydrogen sulfide is an amazingly toxic gas, but that toxicity is exceeded by its pungent rotten-egg odor. The gas will have an exceptionally strong odor, and will seem overwhelming at levels well BELOW toxic amounts. If you can smell this stuff without it literally taking your breath away, it won't be at a harmful concentration.

In FW, these creatures do not exist except for maybe Maylasian trumpet snails, which can totally infest one's tank, making them undesirable to most.