Words on bio-active sand

[Greenmaster]

I know that wiki isn't always right but here is something from the world according to wiki.
hydrogen sulfide
Sulfur reducing bacteria
Sulfate reducing bacteria

About the facultative and obligate:
There are many different types of bacterium in the world that react with oxygen in many different ways. There are, Obligate aerobic, Obligate anaerobic, Facultative, Microaerophiles, and Aerotolerant bacteria

I know that the nitrate to nitrogen bacterium has specimen in at least two of these categories obligate anaerobic (means they are harmed by the presence of oxygen) and facultative (means they can use oxygen and even grow better/prefer it but with the lack there of won't hurt them) in the case of this class of bacterium, nitrate can be used to facilitate it's growth, nitrate is less efficient and thus the bacterium grow and reproduce slower then if it could use oxygen instead.
There is also similar bacterium that uses sulfur or sulfate. There are many types of bacterium that use those two elements (nitrogen and sulfur) to generate energy when oxygen is not present.

Neither one can use nitrogen or sulfur in the presence of oxygen but both have facultative and obligate anaerobic strands.

Fishguy2727 if you have something that says that there are no hydrogen sulfide producing bacterium that fall into the facultative group, I would be interested in seeing it...
Also I enjoyed this debate. I believe debate is one of the best ways for people to learn the truth... both sides state their beliefs and then try to back it up with facts, I find these enjoyable pastimes (and for the record I am not a biologist or microbiologists... heck I haven't and will never graduate... but I do read and I like to learn, again I thank you for this debate)

 

[Fishguy2727]

The best example I can think of that shows that they are different and that their oxygen usage is not exactly the same is the use of air tube coil denitrifiers. In these denitrifers water is slowly run through coiled air tube. The beginning of the tube will have nitrifying bacteria that use up oxygen. At the end you should have denitrifying bacteria that use up the nitrate. However, if the tubing is too long or the flow is not fast enough you will allow for hydrogen sulfide producing bacteria to grow after the denitrifying bacteria.

 

[Greenmaster]

Okay... but that is just rumor/opinion and not really based on facts... I find that there are lots of "facts" in this hobby that are not based on anything but opinion and that leads to a lot of misinformation and confusion. As far as your example goes... I'm not quite sure how people have determined that their setup was producing hydrogen sulfide or not, but many things in this hobby people don't know why it happens so they find something to blame... that's how most reefing myths are brought about.

It is true that hydrogen sulfide is dangerous, not just for your tank but also for your health. That's one reason not to have any kind of de-nitrifying bacteria. And there are many setups that have nothing in the way of nitrate removal except water changes and the little bit that happens in LR. The reason that a DSB can be so risky is you can have a bubble of hydrogen sulfide build up in the sand, then be released into the tank and get trapped on the way up it will then dissolve into the water column and that could potentially be a problem. If you have good water movement, high turnover, and good gas exchange it should be okay. But it is a risk. One of the major benefits of the coil type de-nitrifiers is that after it has left the coil you can then have it agitated or aerated (put it through your skimmer) at that point all the nitrogen gas and hydrogen sulfide gas gets released from the water and you have good clean nitrate, nitrogen, and hydrogen sulfide free water.

I hope this is clear enough and that everyone can understand. If you have any questions at all about these please feel free to ask about them I'll try to do the best I can. If you want to PM me to ask a question that's okay too but I prefer to answer them here for everyone to read put in their two cents and help everyone to gain knowledge.

Truth is always served by great minds,
even if they fight it.
Jean Rostand.

The pursuit of truth and beauty is a sphere of activity in which we are permitted to remain children all our lives.
Albert Einstein.

I believe that it is better to tell the truth
than a lie. I believe it is better to be free
than to be a slave. And I believe it is better
to know than to be ignorant.
H. L. Mencken.

The knowledge of truth, combined with the proper
regard for it and its faithful observance,
constitutes true education.
Joseph F. Smith.

 

[Whobe143]

Well my friend gave me some gravel stones that are slightly large but it does say on the back that minerals on the rock may mess up the ph. Should I use this?

 

[Whobe143]

I also have an under gravel filter should I use this or not?

 

[Whobe143]

Well my friend gave me some gravel stones that are slightly large but it does say on the back that minerals on the rock may mess up the ph. Should I use this?

Nevermind.

 

[Greenmaster]

I also have an under gravel filter should I use this or not?

Under gravel filters can get plugged fairly easily and they attract detritus... with that said. I'm not completely against them as long you have a second filter. I don't have much experience with them and many people say not to use them because of the two reasons I mentioned. As I have said the choice is ultimately up to you. If you are leaning towards using it I would do some research first... or start a new thread on under gravel filters, you should get a good response.