# Sand and Anaerobic pockets??



## SearunSimpson (Jun 5, 2007)

I've never experienced anything of great concern, but then again I take caution anyways. I usually have corries sifting sand, snails tunneling, plants rooting, and during re-scapes or planting the sand is getting moved. 
Whether or not it is a serious issue, it's one I'd rather err on the side of caution...


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## lipadj46 (Apr 6, 2011)

If you use quikrete playsand you will see anaerobic sand guaranteed. That stuff is nasty.


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## Higher Thinking (Mar 16, 2011)

Heavily planted tanks do not suffer from anaerobic gases as the roots dump oxygen into the sand...so I've been told. In non planted tanks anything over 3 inches would benefit from something stirring it up occasionally and cory's ain't gonna do the trick. The anaerobic activity takes place much deeper than they go.


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## tuffgong (Apr 13, 2010)

I think you get anaerobic spots when the grain of sand is too small and causes the sand to compact which creates more resistance for root growth.


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## ReefkprZ (Aug 21, 2010)

Higher Thinking said:


> Heavily planted tanks do not suffer from anaerobic gases as the roots dump oxygen into the sand...so I've been told. In non planted tanks anything over 3 inches would benefit from something stirring it up occasionally and cory's ain't gonna do the trick. The anaerobic activity takes place much deeper than they go.


Actually that's backwards, plant roots take IN oxygen. the leaves use co2 and the roots use oxygen. so a heavily planted substrate is more prone to anaerobic conditions. Which can kill roots.


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## ReefkprZ (Aug 21, 2010)

Yoemen66 said:


> I mean I really don't ever read anything about anaerobic die offs? It sounds like the boogey man that someone reads on a forum and continues to spout off and it grows without any evidence.


if you stay within recommended depths of substrates anaerobic conditions aren't a big issue. 3 inches is about deep enough to plant most things without worrying about anaerobic conditions. 6 inches and you could have issues, and yes its a real situation, not just a boogy man set up to scare gullible aquarist.


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## HypnoticAquatic (Feb 17, 2010)

i can say i have experianced it, it has many factors that play into it type of substrate, grain size, how planted it is, how often wc an rescapes, fauna, how much fauna, mulm/sediment ext ext. so the boogie man is real lol 
as for loss i have only lost some glosso an a few other plants no fauna an that is with mts in my tank to stir it up. so some people can avoid it while others run into it its just life learn how it happend an move forward.


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## vespers_ (May 6, 2011)

if you're worried about it, just poke the substrate with a chopstick or skewer when you do a water change.


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## Yoemen66 (Apr 28, 2011)

I am by no means worried about it. It is just something I always see someone throw out on message boards about the idea that sand is a concern with anaerobic activity, but have never seen anyone who actually new of it happening.

As for the roots, yes, they use oxygen, but just like in terrestrial soils, they break up the soil and cause air pockets to form which allows oxygen and other gases to penetrate the soil deeper. The roots basically prevent the soil from compacted that much.


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## ReefkprZ (Aug 21, 2010)

so let me get this straight, your 3-4 inch sand bed has never gone anaerobic so your pretty much disclaiming the possibility as a boogeyman. gotcha. with science like that... seriously though.

I dont see why you find it hard to believe that in deeper beds anaerobic conditions are a real danger. do some reading, not just in the forums but a couple scientific journals..


> About terrestrial soils> springerlink
> Anaerobic conditions in soil affect plant productivity as well as organic matter and nutrient dynamics. Anaerobic processes often dominate biological and chemical features of flooded and poorly drained soils but in well-drained soils, anoxia is restricted to small zones and to limited periods.


I dont think the soil in our fishtanks can be considered well drained.
for the most part IF a section goes anaerobic only part of a plants root mass may be affected, simply slowing growth untill either: A the anaerobic conditions cease, or B the roots grow out in another direction, above the anarobic pocket etc. can it happen yes can it kill plants sure, is there going to be a mass die off of an entire tanks worth of plants kicking the bucket at once... not very likely. this isnt the texas chainsaw guy running around hacking plants off at the nub. anaerobic conditions and bacterial growth to not happen like flicking a light switch, it takes several weeks of proper conditions for the bacterias to even form...but it can kill plants. not gauranteed to but it can.


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## Rainer (Jan 30, 2011)

Yoemen66 said:


> I am by no means worried about it. It is just something I always see someone throw out on message boards about the idea that sand is a concern with anaerobic activity, but have never seen anyone who actually new of it happening.


Does gravel count?


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## ktownhero (Mar 21, 2011)

The anaerobic issue is way overblown. Use the recommended amount of substrate and enjoy your tank...


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## Rainer (Jan 30, 2011)

My standard-sized gravel substrate was bubbling hydrogen sulfide a few weeks ago. Luckily it was on a light planted area.


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## HypnoticAquatic (Feb 17, 2010)

ktownhero said:


> The anaerobic issue is way overblown. Use the recommended amount of substrate and enjoy your tank...


 this is the wrong way to think about it as i have less than 2-3inch so why do i have it? its simple like i said there are factors and when they are met they can an will cause anerobic spots its simple science an that it why we use filters, clean the tank, do wc's, an rescape ext ext. all of those things can and do help to minimise the "risks" of having anerobic spots. imo its like not changing the oil in your car, you let it go yes it will run for quite some time but when it fails and it will it does so with sever damage an then you have to spend lots of time cleaning an replacing everything so its all up to you.


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## Yoemen66 (Apr 28, 2011)

woah, I never said I didn't believe it could happen. I wasn't asking out of concern either. I was asking from the purpose of a discussion on the matter as I have read several people over the years bring it up, usually with the statement they have never had an issue with it. so I was asking if anyone had a problem with it. 

I am only going on my experience but enjoy a nice academic discussion on the possibility of it.

My idea is still that with heavy root penetration your soil wouldn't go anaerobic due to the soil not being compacted enough to prevent O2 exchange in the pockets. 

I never once said I thought it couldn't happen, but that I had never seen anyone state it had happened.

geez.


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