Anaerobic zones

[cerianthus]

Trying to achieve a perfect balance of anaerobic zones in the substrate is pretty much impossible. There will end up being either too many toxins in the tank or the anaerobic zones won't build enough to begin using nitrates. Either way, they're not something I would rely on, which is why all of my tanks are constantly stirred by Malaysian trumpet snails.

As I have mentioned earlier, very unlikely such process will take place unless have Deep Sand Bed and/or tank has been really neglected. And from reading members postings, I doubtful of such mishap, actually I was telling myself that some may be doing to much maintenance on the tank, lol!
Anyone with deep sand bed, look from under the tank w/ flash light, which can be easily observed (Dark/Black Patches)when not properly maintained.
When such Dead Zones are noticed, simple GENTLE Vacumming will disturbed the DEAD ZONE and removes possible Toxic GAS. Can check for possible odor in bucket .
Having fish/snail which will constantly disturbed the substrate will definitely help you in keeping substrate in AEROBIC CONDITION as I am using CLAMS in S/W to do the same and also filters the water.
No intention of scaring anyone as well maitained tank will avoid such mishaps.

 

[prairielilly]

Not trying to be argumentative Cerianthus, really, but the majority of us I believe have our tanks parked on something solid, and then they're full of water and so more than a little heavy; there's no way I could look at the bottom of my tank from underneath without emptying it and tearing it down and moving it; I don't see any need to do so. When I gravel vac (once a week) I make sure I stir everything up really well and get it as clean as possible. I'm therefore not worried at all about anaerobic gas pockets.

One note on the exact measurement of mL's etc... when I was fishless cycling I got something at the grocery store called a 'flavour injector' - basically a 20 mL plastic syringe with a blunt needle on the end, used to inject broth etc. into turkeys, roasts and the like. I removed and discarded the needle and voila, had a very easy way to measure out exactly how many mL's of ammonia I needed. I paid less than $5 for it. That said, in terms of water testing I just make sure the bottom of the meniscus is around the marked line on the test tube and don't worry about it too much.

 

[sirdarksol]

A few things, Cerianthus:
First of all, vacuuming is very unlikely to get all of the toxic stuff (and it's not all gas) in an anaerobic zone. Some of it is going to get into the water.

Second, yes, I do realize that snails help keep the sand bed stirred up, which is why, in the post that you quoted, I say "my tanks are constantly stirred by Malaysian trumpet snails."

Third, as I said, this is a balance that is very difficult to maintain.
You're talking about deep sand beds, which are sometimes used in reef tanks (but often avoided because of the problems we're talking about). The thread this originated in was a primarily freshwater discussion, however, and involves gravel as much as (or more than) sand. In gravel, more waste is likely to sift down into the spaces, creating larger pockets and larger quantities of toxic material much faster.

Lastly, are you saying that you doubt that anyone has ever had an anaerobic pocket kill off the fish in their tank?

 

[cerianthus]

Not trying to be argumentative Cerianthus, really, but the majority of us I believe have our tanks parked on something solid, and then they're full of water and so more than a little heavy; there's no way I could look at the bottom of my tank from underneath without emptying it and tearing it down and moving it; I don't see any need to do so. When I gravel vac (once a week) I make sure I stir everything up really well and get it as clean as possible. I'm therefore not worried at all about anaerobic gas pockets.

One note on the exact measurement of mL's etc... when I was fishless cycling I got something at the grocery store called a 'flavour injector' - basically a 20 mL plastic syringe with a blunt needle on the end, used to inject broth etc. into turkeys, roasts and the like. I removed and discarded the needle and voila, had a very easy way to measure out exactly how many mL's of ammonia I needed. I paid less than $5 for it. That said, in terms of water testing I just make sure the bottom of the meniscus is around the marked line on the test tube and don't worry about it too much.

No, what I meant was look from inside the cabinet. I would not have dreamed of going thru all that work for possible dead zone. Use the flashlight if on cabinet. This is impossible if tank is on DIY/Entertaiment Cabinet. Most cabinet/metal stand made for Tank are open so can be viewed from under the tank.

 

[cerianthus]

A few things, Cerianthus:
First of all, vacuuming is very unlikely to get all of the toxic stuff (and it's not all gas) in an anaerobic zone. Some of it is going to get into the water.

Of course, but most concern will be H2S Gas if, I said if, ther are really dead zones.

Second, yes, I do realize that snails help keep the sand bed stirred up, which is why, in the post that you quoted, I say "my tanks are constantly stirred by Malaysian trumpet snails."

I meant to say I concur.

Third, as I said, this is a balance that is very difficult to maintain.
You're talking about deep sand beds, which are sometimes used in reef tanks (but often avoided because of the problems we're talking about). The thread this originated in was a primarily freshwater discussion, however, and involves gravel as much as (or more than) sand. In gravel, more waste is likely to sift down into the spaces, creating larger pockets and larger quantities of toxic material much faster.

I have tried deep sand bed for F/W planted tank and others!

Lastly, are you saying that you doubt that anyone has ever had an anaerobic pocket kill off the fish in their tank?

Either my writing skills are terrible or I dont know what! What i meant was when one keeps up with proper routine maintenance, it is very unlikely anyone will experience such mishap (dead zones) as I have experienced. Long ago, I was trying to experiment to minimize water changes by having created Dead Zones to knock off NO3 (What I know and learned so far from reading/experimenting fish pahtology, anatomy and physiology of Teleosts is that NO3 is not as critical as keeping fish in extreme pH, my opinion, so need for arguments). This along with Protein Skimmer for F/W, Ozonizer, Air Pump, Air dryer, O3-O2 reactor, Carbon chamber/reactor, ORP controller, etc.
My conclusion was, unless for large volume tank, be it fw or sw, as I read in newspaper long ago where one guy had cylindrical tank from basement to top upper floors mailny for Shark and Stingray, Dead Zone theory was inapplicable for most small F/W tanks. Thus I came up with so called River System where aged water can be dripped into tank, f/t or p/t, thus less work carrying buckets. I hope my thoughts have not caused any misunderstanding.