hydrogen sulfate discussion

[spykes]

hey has anyone readed the latest edition of reefkeeper? hydrogen sulfate is some deadly stuff, many of our aquariums dont have the ability of converting H2S into thiosulfate, or ironsulfate. Summarizing it our body uses hemoglobin 4 iron grouped molecule to remove stuff harmful to our body such as Co2, iron can also drive down sulfate, which is added into the aquarium by many products such as epsom salt, as a mitochondria inhibitor, it's also a ATPase inhibitor. I find many aquarist, doesnt know the chemestry behind the tank, so i like to summarize some of the articles, and if someone like shaun and others are better then me and can correct me, i can learn more too! we can discuss this further if anyone has any knowledge of this chemestry. On with the show, H2S can be loosely attached to iron, so iron oxide, which is phosban can also remove H2S, as well as desolved oxygen.

Sandbed problems!

many people dont understand the H2S buildup underneath their sandbeds, the sandbed itself contain anerobic bacteria. This bacteria converts no3 to H2S like many other form of denitrators. If you remove a sandbed please dont sell it to people as livesand, or dump it back into your own tank, this sand was anoxic(absense of oxygen) once you take it out sulfate combines the H20(water) quickly grabs a oxygen ion instead of the sulfate. 2 H2S + O2 ? 2 H2O + 2 S which allows a black stuff to form and quickly smell like crap, dont buy used sandbeds or reuse sandbeds, if you do please read dissolved organics. People whole pulled out their sandbed and didnt smell, wait couple of hrs and then look at the color changing and oder creating it undergoes.

he aquarium had a bed of 1-2 inches of fine oolitic aragonite sand and contained wild Florida live rock (not aquacultured) placed in the tank when it was started. As I dug through the sand, I found no black areas, and detected no unpleasant odors. None of the rock had any apparent grey or black discoloration. All rocks were a uniform tan color on areas not exposed to light. The sand was put into a bucket and remained in the garage for two weeks. When I then dumped the sand out behind the garage, it was grey and it stank to high heaven. Clearly the processes leading to hydrogen sulfide formation were not taking place in the sand bed in the tank, but that same sand quickly became anoxic when removed from the aquarium.

please read the bottom part of the article of http://www.reefkeeping.com/issues/2005-12/rhf/index.php#1

and lets have some discussion about our sandbeds!
sorry for being bored hehhehe

 

[ShaunW]

Dave, awesome subject. It's late right now and just saw your post, so I will contribute to the discussion tomorrow when I get to work.

 

[alrha]

nice post.

would it make sense to stir a tiny bit of the sandbed from time to time to release any H2S that may be building up in it?

 

[spykes]

alhra over the years our rocks and sandbed will have deep pockets of sulfate, if it wasnt to early for you, the reefkeeper issue has pictures of the florida keys rocks, a perfect calcium bicarbonate rock is whiteish yellowish, those brown to black lines are sulfate. yes over the time, the ministirs will eventually get the H2S out into the water, but throughout the year this will happen anyways thru a process called defusion where the higher concentration will go to a lower concentration. The hydrogen bonds are weaker then most people thing, this dipolar molecule breaks down and reforms every microsecond. I would think sulfate can travel and not stay forever in our tank. if ti doesnt have somewhere to go, that is a bad thing hehhe. look at this guy's sandbed.

 

[spykes]

Dave, awesome subject. It's late right now and just saw your post, so I will contribute to the discussion tomorrow when I get to work.

cant wait till your crotique me. this is the main reason why i go with a bear bottom, not the higher nutrients reason, but a real buildup of sulfate, though our rock needs a good beating, that's why i burn the rock till it's white with co2 or acidic acid hehehe.

 

[alrha]

this is what i figured. as long as there is a turnover in the sand bed, the H2S would be getting released and not continue to build up forever. the rock as well should be releasing it as long as there is flow through it.

It seems that the issue would arise if a massive amount would be released all at once due to a significant disturbance of the sand bed or live rock.

and why cant you reuse old sand? it doesnt bind to the sand, does it? from what i understood you can easily smell it, but once given the opportunity to oxidize, it is no longer an issue, no?

 

[spykes]

once it oxidize your sulfate would turn from 4 H2S to H20 and sulfate so4. which becomes a solid. sulfate is toxic to lifeform, in any great amount, a undisturbed sandbed would have a layer which allows only small amount of difusion, once your sandbed is axion, everything is mixed and turns bad and you dont know what else is under the sublevel of your substrate. alhra the point is where is it releasing to? sulfate is a metal, i persume you cant skimm a large amount out. your caulpra wouldnt absorb it, where will it go? remember this isnt nitrogen gas from a sandbed which releases into the atmosphere. This is why i recommend people to start with coarse agronite sand, and new sand as well, add only a cup of livesand from other user's tank. make sure it's white on top you dont want black sand. shows a disturbed sandbed and well aged. most of the time your getting bacteria from your rocks which is enough to seed your sandbed. dont go crazy hehe.

it doesnt bind to sand i wouldnt think so, but it would solidfy under creaves and the gas pockets of your sand.

 

[herman]

My last DSB Tank crashed all of a sudden. Withing a couple of hours a pristine clear tank turned into a toilet. The DSB featured a plenum where anarobic conditions are found. One day the plenum got breached and the rest is history.

I have never gone back to DSB after that. The horor of seeing your tank detiriorate so quickly.

Whenever one cleans out a tank they will eventually reach the sand and when they start to scoop it out inevitably they will reach a portion that smells like a nasty public toilet. Its for this reason that I worry when people who have an established DSB decide to convert the tank to BB by means of siphoning out the sand.

I do hope Solbby can chime in as to whether that is an advisable method and also how quickly the reaction takes place.

 

[NYPDFrogman]

great thread!!!!

I'm no chemistry major but I understand whats happing here.
I'm not a big fan of DSB's and yes I know this can be debated forever.
but I can share some expierence. as I have said before I made my living diving in and around the waters here in NY.
as most of us know, newtown creek, coney island creek, spring creek smell horrible at low tide. Most believe that the stench is caused by polution.
in reality it's not it's hydrogen sulfate
in the late 80's most of the dive team was getting sick, stomach and digestive problems. We got together had water samples taken and found someone to analize them and we got the lab at Jacobi hospitol involved.
it turns out it wasnt the water that was making some sick but the bacteria that lived on the lines and equipment that was. the water alothough not cyrstal claer was in pretty good shape,
thats when I learned about hydrogen sulfate. it's naturallly occuring in areas where there isnt a sufficent circulation of water.
during the recovery of flight 800 we were 12 miles off shore in 125-135' of pristine water, yet when I got out of the water my hands had the riotten egg smell, we were sifting and stiring up the bottom during our sreach.

IMHO the best way to eliminate it in a reef aquarium is the absence ot a sand bed and lots of water movement, not between the sump and tank but within the tank

 

[cali_reef]

great thread!!!!

I'm no chemistry major but I understand whats happing here.
I'm not a big fan of DSB's and yes I know this can be debated forever.
but I can share some expierence. as I have said before I made my living diving in and around the waters here in NY.
as most of us know, newtown creek, coney island creek, spring creek smell horrible at low tide. Most believe that the stench is caused by polution.
in reality it's not it's hydrogen sulfate
in the late 80's most of the dive team was getting sick, stomach and digestive problems. We got together had water samples taken and found someone to analize them and we got the lab at Jacobi hospitol involved.
it turns out it wasnt the water that was making some sick but the bacteria that lived on the lines and equipment that was. the water alothough not cyrstal claer was in pretty good shape,
thats when I learned about hydrogen sulfate. it's naturallly occuring in areas where there isnt a sufficent circulation of water.
during the recovery of flight 800 we were 12 miles off shore in 125-135' of pristine water, yet when I got out of the water my hands had the riotten egg smell, we were sifting and stiring up the bottom during our sreach.

IMHO the best way to eliminate it in a reef aquarium is the absence ot a sand bed and lots of water movement, not between the sump and tank but within the tank

I agree with you on this one 100% but I still have a deep sand bed in my fuge. I can change out the sand by isolating it, nothing will be polluting the main tank water if I wish to do so. I am keeping the DSB in my system because I feel it still have some benefit in keeping down NO2 and NO3 (either as a sink or processor) with my large fish population and is providing a breeding ground for certain critters.

 

[House of Laughter]

Dave, DSB is still good, if you have the appropriate critters to stir up the mix - problem, is that there are never enough critters for the square inches we put into our tanks.

I did exactly what Cali does - DSB in the fuge remotely - I might add that I observed my tank is doing much better and I have been also monitoring other pieces of the system - the fuge has just begun to denitrify and I can see the bacteria building up in there.

It will be changed before it gets to the point where it destroys the entire tank, likely 3-4 years.


Herman, the latest on the Jalabert method is to secure a 1/4 siphon hose to the plenum and once a year or so, siphin out the nasty water beneath the plenum. Just an FYI

House

House

 

[herman]

Dave, DSB is still good, if you have the appropriate critters to stir up the mix - problem, is that there are never enough critters for the square inches we put into our tanks.

I did exactly what Cali does - DSB in the fuge remotely - I might add that I observed my tank is doing much better and I have been also monitoring other pieces of the system - the fuge has just begun to denitrify and I can see the bacteria building up in there.

It will be changed before it gets to the point where it destroys the entire tank, likely 3-4 years.

House

How did you deal with the super deep sandbed/plenum on the 92g? Did you ever have any problems with that?

 

[NYPDFrogman]

I agree with you on this one 100% but I still have a deep sand bed in my fuge. I can change out the sand by isolating it, nothing will be polluting the main tank water if I wish to do so. I am keeping the DSB in my system because I feel it still have some benefit in keeping down NO2 and NO3 (either as a sink or processor) with my large fish population and is providing a breeding ground for certain critters.

I should have added I also have a DSB in my fuge which can be isolated from the tank and rest of the sump. I agree it definitly has it's advantages and place in a reef tank.
I also aggree with Jim in regards to having enough sand stirers. I'd like to add more
I have a ton of pods in my tank at night it looks like snow

 

[spykes]

listen i never said sandbeds were not good, but people said sandbeds build up hydrogen sulfate due to the lack of circulation is right, all sandbeds will lack circulations or else they will not work! underneath the DSB there will be 0 circulation of water, everything is going under diffusion from the chemical gradient of water! if you have flow in the DSB it will not work like a DSB but like a fluidized sandbed. remote sandbeds are still benifitical due to remote removal, but sulfate will still build and if you start a DSB with live sand, IE not dried agronite sand, then you will have a greater sulfate problem. god knows how long the sand had been in the bag.

Im not promoting BB or DSB, etheir one is fine, when they are new and taken care of. good husbandry goes along way. Im trying to spread some chemstry knowledge withing the group of more of the advance reefers. it is a very hard hobby, and the best we can do is research and learn more.

herman i think this is a great thread because im finally reading a thread that is not linking towards anyone's personal life.

Cali i think your system is awsome, dont change anything
but i hope people understands disolved organics, when organic phosphate is broken down, the bacteria that does this process utilizes O2(oxygen) which allows the byproduct of Co2. This process with not only lower your PH, but increases the speed of lowering your ALK! that is why i find people with excessive bacterial filtration undergoing more consumtion of ALK.

The bacterial that creates H2S from a byproduct is also related to the downfall of ALK, your sandbed utilizes aerobic bacterial under the superfical layer of the sandbed(upper disturbed layer) and that makes your anerobic bacteria consume it's byproduct which is No2 and NO3. Creation of H2S then is undergo. If you quickly look at this more NO2 and No3 means more sulfate and more alk drivin down, everything is pretty much correlated.

 

[herman]

Interesting!!! Threads like this one really gets you thinking about how every little thing in our biotopes is correlated. One small change here will have a drastic effect there.

Normally I would be going to bed right now, but I am going back to my old logs of my tank to see where I went wrong.

Also spykes - good point on the live sand in the bags. Never thought of that. I see some stores not rotating their stocks as far as first in first out and some poor guy will get the 2 year old bag of live sand.

 

[herman]

Quick Question: What exactly does H2S stand for?

what is the difference between sulfate, sulphate, sulfite, sulfide? Looking around I get confused because I see H2S reffered to as all of the above.

Am I correct in saying that:

S = Sulfate
SO4 = Suilfide

and all others are spelling variations?


Thanks

 

[NYPDFrogman]

David I dont think anyone assummed you were addressing sandbeds, pros or cons. I would say that DSB's are directly related to hyrdogen sulfate. I introduced the topic of DSB's in a tank maybe that where it drifted.
as I said before they definitly have thier place in reef keeping I think the question is controling the build up of hydrogen sulfate within the DSB
this a great thread!

 

[cali_reef]

I would say that DSB's are directly related to hyrdogen sulfate.

Frank, IMO it is the other way around, hydrogen sulfate leach is directly related to the so called DSB. Our DSB are not deep enough so the hydrogen sulfate is coming back up once the little sand beds are filled with it.:approve:

 

[alrha]

nice to have these advanced threads evey now and then.

(do we need an "Advanced Forum" now?)

how is H2S addressed in tanks with DSB? Wouldnt activated carbon be able to remove it (when in solution)?

 

[herman]

Substrates in corralation to H2S

Never mind my last post. Let me see if I understand this properly.

We have a lot of discussions on the board as to BB and DSB. When we discuss any kind of Sand Bed we always go to the grain size of the sand. We all agree and avoid silicate based substrate and generally go with aragonite.

Coarse substrate will eventually lead to debris collection and eventually lead to oxygen starved (anaerobic) conditions in the lower levels which will lead to production of H2S

Fine subsrtate will basically lead to the finer partices building up on the bottom thus producing silt which does not allow O2 to diffuse the bottom layers creating anaerobic conditions inevitably leading to the production of H2S.

In my understanding sand is good for creating anaerobic conditions for denitrification, but it is doomed to "crash" eventually.

So the best way is to have a BB Tank with a separate DSB system attached to it where the DSB can be changed if needed without disturbing the main tank.

Is that about right?