Controlling pH with Sulfur?

[digidana]

does anybody know anything about this? i've been doing some reading, trying to understand the pH, alk, calcium stuff and came across this:

"A newer method of aragonite dissolution is to use sulfate to depress pH within the reaction vessel. this method is actually a spin-off of a sulfur-fed denitrification filter system, in which a sulfurous medium is placed within a semi-enclosed vessel and utilized as a growth and colonization medium for the bacteria responsible for nitrate reduction. When the flow rate of water through the medium is properly adjusted, the result is a total reduction in nitrate (into nitrogen gas) and the release of sulfate. If this sulfate-laden (hence low-pH) water is then passed through a column of calcareous media, the result is dissolution of the media, producing the same results obtained with a traditional calcium reactor but at a fraction of the cost, with no associated COx-related issues, and with the total eradication of nitrate. This system represents the current cutting edge of reef aquarium water care technology."

does anybody use this method or now how its put together?

 

[ct_vol]

I think you are misunderstanding the concept... The sulfur isn't what lowers the pH... You hook up CO2 to the reactor which lowers the pH and then breaks down the sulfur, then runs through Calcium reactor media which is then broken down... So the Sulfur doesn't control the pH, its actually the opposite all within the reactor, not the aquarium...

I know Matt has a DeNitrate reactor... I don't know if he ever set it up...

Here are a few kits sold by Premium Aquatics

 

[digidana]

yeah, i'm not sure i get it. to me it sounds like water that's high in sulfates increase the speed that the aragonite dissolves (because of the lower pH). so would you use a denitrification filter to increase the sulfur level to run through a calcium reactor?

it talks about calcium reactors separately, it doesn't sound like they're connected in the book.

 

[cee]

The way I read it, you don't add CO2. The article specifically states "no associated COx-related issues". The bacteria breaks down the media and nitrates, producing nitrogen gas and sulfate as by-products of the nitrate conversion process. Since sulfate ions are positively charged, they combine with hydroxide ions and lower the pH to the point where the aragonite in the effluent is dissolved. My only concern would be what does the sulfate hydroxide (or whatever the byproduct is called) do to the overall water chemistry. Nitrate conversion by bacteria is well established and the media, if properly chosen, could produce the aforementioned chemical reactions.

Dave

 

[digidana]

right! that's how i understood it. I don't know about the sulfate byproduct.

i can't find anything on the net about it. there is a footnote that says its pretty much new to aquarists, but that its been used for over a decade in large-scale aquaria and scientific institutions throughout parts of europe.

i wouldn't have a clue how to set it up tho. it just sparked an interest.

 

[ct_vol]

I guess I must have misunderstood... lol I guess I just assumed that they were talking about Nitrate reactors, as that is the only way I have read about using sulfur in an aquarium... However, I still believe there are other compounds and buffers used to maintain pH that are more beneficial to the aquarium than sulfur... But that is JMO...

 

[KafudaFish]

You might check out the DIY sulfur denitrofier thread. I am leaving work or I would find it for you. They discuss this in great detail. One thing about the system is that it increases your alk demands. Also you must adjust the flow through the chambers and measure your system's alk because it can go very low.
The second chamber is more of a buffer for the low pH water coming out of the sulfur chamber. You could build this system for around 100 bucks incluing the sulfur beads and the Ca media. Good luck.

 

[ct_vol]

Here is a link to the thread Mike was referring to...

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1400576

Happy Reading

 

[KafudaFish]

Thank you Randy. I sent you a pm last week did you get it?

I know that this has been used in sewage treatment plants. I have an article about one in Florida and it was very efficient in treating the different forms of nitrogen. I don't remember how they dealt with the low pH water though. It probably went to a settling pond or something before being discharged into the local waterways.

One thing about using this from the above thread: Most people ran theirs for a short time like a month or so then after nitrates were down to "0" they took them off line and stored them. This was a method for people with high nitrates that tried everything else but could not get the levels to decrease.

As I said earlier you can buy a kit for $$ or make one for very cheap. If it is something that you have to take off line why spend the extra $.

Please let us know what you do.