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Thanks Diana for posting here. The info about the clay is a mistake I was about to make. I have been soaking my soil and will have soaked it for 1 month before using it in my tank. I will update here if there is any good news about doing that. (mainly the ammonia problems I hear of.) If you read this Diana I am really looking forward to you visiting our club in Indianapolis in November. I almost waited to start my tank until then but I can't help myself wanting to do it sooner.:D
 

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Speaking of soaking miracle grow potting soil, I have been trying simply to wet some this morning in order to make a little grow out tub for the yard. (I am using a cement mixing tray and covering it with a film of plastic.) After about three hours most of it is still floating and parts of it are still dry as a bone.
I've been soaking my mgocpm for about 16 hours now, and mine is in a very similar condition. I've got it in a 30 gallon trash can outside. There are about 3" of material floating on the surface, about 1-1/2" to 2" has sunk to the bottom, and about a 6" layer of water in between. I stirred it quite thoroughly when I first started, then let it sit overnight, and have stirred it a couple of times so far today to see if I could get anything more to sink. Is this normal?
 

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Discussion Starter · #123 ·
Yes. It will not hurt anything to let it sit overnight again. Some more of the woody chunks may become water-logged and sink.

But then you will need to pour off the floating stuff. Tip the container gently on its side, and slowly pour out the surface layer of floaters. Continue pouring until you just begin to get some of the sinking soil at the bottom. Then stop pouring and refill with water. Repeat every day for at least three times.
 

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I've been soaking my mgocpm for about 16 hours now, and mine is in a very similar condition. I've got it in a 30 gallon trash can outside. There are about 3" of material floating on the surface, about 1-1/2" to 2" has sunk to the bottom, and about a 6" layer of water in between. I stirred it quite thoroughly when I first started, then let it sit overnight, and have stirred it a couple of times so far today to see if I could get anything more to sink. Is this normal?
I think letting MGOC stuff float on the surface won't get the gas out efficiently. You need to somehow hold the soil underwater and let the weight of the water and the increased water pressure squeeze the gases out. If you just let the soil float on the surface, it will take forever for it to degas.

In my tank setups, I degas the soil automatically when I put a 1" gravel layer over the 1" layer of wetted MGOC. The gravel holds the soil down as I slowly and carefully fill the tank with water. After that, the weight of the gravel and the water helps force the gas out of the soil so that the soil quickly degasses and does not float.

Another possible solution -- one I may try next time -- is to add the soil to the tank, wet it as usual, and then cover it with something heavy (i.e., rocks, dinner plates, casserole dishes, etc). Let it sit overnight and then add the plants and gravel.

I hope this makes sense.
 

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Thanks Diana for posting here. The info about the clay is a mistake I was about to make. I have been soaking my soil and will have soaked it for 1 month before using it in my tank. I will update here if there is any good news about doing that. (mainly the ammonia problems I hear of.) If you read this Diana I am really looking forward to you visiting our club in Indianapolis in November. I almost waited to start my tank until then but I can't help myself wanting to do it sooner.:D
I understand the desire to get a tank going. Ha!

Look forward to visiting your club and meeting the members. Maybe, I should offer to do a quick planted tank setup while I'm there?
 

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I think letting MGOC stuff float on the surface won't get the gas out efficiently. You need to somehow hold the soil underwater and let the weight of the water and the increased water pressure squeeze the gases out. If you just let the soil float on the surface, it will take forever for it to degas.

In my tank setups, I degas the soil automatically when I put a 1" gravel layer over the 1" layer of wetted MGOC. The gravel holds the soil down as I slowly and carefully fill the tank with water. After that, the weight of the gravel and the water helps force the gas out of the soil so that the soil quickly degasses and does not float.

Another possible solution -- one I may try next time -- is to add the soil to the tank, wet it as usual, and then cover it with something heavy (i.e., rocks, dinner plates, casserole dishes, etc). Let it sit overnight and then add the plants and gravel.

I hope this makes sense.
Thanks Diana. I don't think I've seen anyone in this or other forums mention a situation where nearly 75% of their mgoc never sank (now for about 40 hrs of soaking in my case), and I was starting to worry I might not get much of anything useful out of this bag. I'll try to find something with which to hold it under the water and post my results.
 

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Thank you so much for sticking with this thread Michael!

I'm preparing to start up an NPT (been a few years since my last one) & was looking at this "humus" potting soil http://www.amazon.com/gp/product/B002JLEDQ0/ref=s9_simh_gw_p86_d0_i1?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-3&pf_rd_r=1PDHC268QQNJVZ5YRW1V&pf_rd_t=101&pf_rd_p=470938811&pf_rd_i=507846 & would appreciate your thoughts on its suitability. I'd probably blend with either laterite or some of the Caribsea Torpedo Beach sand I'm planning to use as a cap.
 

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Discussion Starter · #128 ·
You're welcome!

I don't know how much bat guano they put in this soil, but that stuff is HOT! It approaches synthetic fertilizers in nutrient level. Be extremely cautious with this stuff. Honestly, I think you would be much better off with something like a plain bagged topsoil. And it would be much less expensive.
 

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I understand the desire to get a tank going. Ha!

Look forward to visiting your club and meeting the members. Maybe, I should offer to do a quick planted tank setup while I'm there?
I'm sure whatever you decide to do will be interesting to me. I would like to hear more on allelopathy and how plants get their nutrients without adding chemical fertilizer. There is so little information that I can find on those subjects.
For instance I am still unsure if my water is going to supply my tank with enough K. The water I will use has K but the ph is 8.2 so I will have to mix it with RO to get the ph down. It's very confusing for a layman to understand how to interpret well water reports such as K levels in ppm to numbers that I can use to determine if it will be sufficient without adding K.

So I don't hijack the sticky let me add some to the topic. I have had my MGOCPM soaking for 10 days now with one water change. It took several days for a noticeable amount to stop floating that I couldn't even think about pouring off the floaters after even 3 days. Maybe I have a very fresh bag. I am glad I decided to start soaking it ahead of time because it seem to be very hard to get wet.
I also remember in Walstad's book that well decomposed soil should be used. Those of us using MGOCPM are stuck with whatever is in the bag we buy. I hope soaking my soil helps in this aspect as well since I don't have room to wet then dry to speed decomposition.
 

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You're welcome!

I don't know how much bat guano they put in this soil, but that stuff is HOT! It approaches synthetic fertilizers in nutrient level. Be extremely cautious with this stuff. Honestly, I think you would be much better off with something like a plain bagged topsoil. And it would be much less expensive.
Good to know on the guano. Hard to find plain topsoil in less than a giant bag, unless we're talking "potting soil," but I'll mosey on over to my local Home Depot or something & check it out.
 

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I have now been soaking my mgocpm for just over a week, and some of it is finally starting to sink. So far about 40% of it is sitting on the bottom while the rest is still quite buoyant. There's still too much material at the top to try to pour of the water. I haven't been able to find anything quite the right diameter to set on top of the floating material so I can weigh it down like Diana suggested. My next idea was to try to skim it off and put it in some sort of a cloth bag to which I could tie a weight.
 

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Unless your budget is really tight, I suggest you just throw out the floaters.
I guess I'm just a little shocked that my experience seems so different from everyone else's. Unless I'm wrong, isn't the less decayed material supposed to decompose more slowly to keep the co2 cycle going stronger longer. I would think there would be some benefit to having organic material in a lot of different stages of decomposition to start out with to keep the tank going longer down the road. Or is the bottom layer supposed to be used up completely fairly quickly and the ongoing cycle perpetuated only by the fish waste and unconsumed food?
 

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A lot of organics is a problem in any tank. Hence why we siphon the substrate regularly in an unplanted tank and clean the filters. It's all done to prevent organic build up. In a planted tank organics have their benefits being the source of CO2 and minerals, as long as there's an overall balance between amount of organic build up in the soil and flora/fauna choices to cope/process with that amount.

Mineralizing the substrate only converts some of the organics into non-toxic minerals but does not get rid of all of it. This prevents possible excess stuff being released into the water column when flooding the soil, affecting the fauna. Excessive organics and not enough plants can also cause the substrate to become anaerobic leading to release of all types of toxins that can kill both plants and animals.

The other good part of mineralizing the soil is that the wet/dry cycles help wash out any possible artificial chemicals that the soil may contain.

Also, those floating wooden chips and stuff aren't helpful at all. They won't decompose any faster than the driftwood/bogwood one uses for decoration. As Michael says, they are best thrown out.
 

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And yet there seems to be a whole host of people using mgocpm ( I think even Diana herself at times) straight out of the bag with just a slightly longer stabilization time but excellent long term results. So who's right?

According to the information in this thread (and the definition of the word itself) anaerobic conditions are caused by the absence of oxygen in the decomposition environment, not the presence of organics. That's more related to substrate depth than ingredients. Even the driftwood will eventually break down completely, but the small pieces of floating wood in the potting mix will break down more quickly because they're much smaller.

I've also seen journals of numerous tanks that started with fully mineralized soil using recipes found on this and other sites that had some success in the beginning but ultimately had to be torn down prematurely or converted to high tech because the soil had became basically worthless. At least a couple of the people who experienced this ended up deciding to stick with mgocpm straight out of the bag.

I'd really like to hear from people who have real world experience on both sides of this discussion, because a lot of what I've read seems somewhat contradictory.
 

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Discussion Starter · #136 ·
OK, I've used MGOC straight out of the bag and had good results. But my preference now is to mineralize it and mix it with a high CEC substrate for the reasons given elsewhere in this thread.

Everyone is right--either way can work.

"According to the information in this thread (and the definition of the word itself) anaerobic conditions are caused by the absence of oxygen in the decomposition environment, not the presence of organics."

Fresh, abundant organics are rapidly decomposed by aerobic (oxygen-loving) bacteria at first. But those very bacteria can deplete all the available oxygen in the substrate, especially if it is too deep or the cap is too fine or compacted, but even if conditions are otherwise correct. (This eventually happened in my first straight-from-the-bag MGOC tank.) After the aerobic bacteria die off, decomposition continues by anaerobic bacteria, albeit more slowly. Those anaerobic bacteria produce the toxic substances (hydrogen sulfide and others) that are the reason anaerobic substrate is undesirable.

". . .but ultimately had to be torn down prematurely or converted to high tech because the soil had became basically worthless."

Soil never becomes worthless. Even after all the organics are completely decomposed and all the initial nutrients are depleted, the remaining humus and clay minerals retain their high cation exchange capacity (CEC). CEC enables them to absorb nutrients from the water and hold them in the substrate until plant roots can use them. At some point the nutrients must be replenished, but Walstad has shown that fish food can supply all the necessary nutrients for tanks without CO2 supplementation and with low to moderate light.

Tanks can fail for many reasons. If you decide to maintain a soil-based tank with high light and supplemental CO2, eventually it will be likely to need supplemental nutrients as well.
 

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OK, I've used MGOC straight out of the bag and had good results. But my preference now is to mineralize it and mix it with a high CEC substrate for the reasons given elsewhere in this thread.
It has always been my plan to mix my mgocpm 50/50 with STS and cap it with STS for the reasons you've stated previously whether I ultimately ended up putting it through a complicated preparation process or used it dry. Of course I did end up soaking it, and now have basically nothing to show for it. Once all the floaters were skimmed off (which I did just before posting this), I only have enough soil left for maybe a half inch layer in my 24" by 24" tank out of a 32 lb bag. Unless my next bag is totally different, I'm going to end up needing two to three more bags to come up with enough material.

Fresh, abundant organics are rapidly decomposed by aerobic (oxygen-loving) bacteria at first. But those very bacteria can deplete all the available oxygen in the substrate, especially if it is too deep or the cap is too fine or compacted, but even if conditions are otherwise correct. (This eventually happened in my first straight-from-the-bag MGOC tank.) After the aerobic bacteria die off, decomposition continues by anaerobic bacteria, albeit more slowly. Those anaerobic bacteria produce the toxic substances (hydrogen sulfide and others) that are the reason anaerobic substrate is undesirable.
But is this effect exacerbated by the presence of more slowly decomposing organics such as tiny pieces of tree bark in the substrate? And what impact do pieces of driftwood in the hardscape have on this? Would it be better for driftwood to sit on the bottom glass with the substrate poured in around it, or should it rest on top of the substrate to prevent it from contributing to anaerobic decomposition?

Soil never becomes worthless. Even after all the organics are completely decomposed and all the initial nutrients are depleted, the remaining humus and clay minerals retain their high cation exchange capacity (CEC).
Tanks can fail for many reasons. If you decide to maintain a soil-based tank with high light and supplemental CO2, eventually it will be likely to need supplemental nutrients as well.
I suppose these people could have all fallen victim to misinterpretation of circumstances, but it seems like the only people who ever end up satisfied with the long term results all those overly complicated mineralized topsoil recipes are the people who came up with them in the first place.
 

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Discussion Starter · #138 ·
I did not invent mineralized topsoil, but I've had very good results with it. Have you used it?
 

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I haven't used anything yet. This is my first planted tank, much less my first NPT. I'm just trying to learn as much as I can from the experiences of others; so I've read literally hundreds of threads on dozens of sites trying to be as informed as I can be. I don't have the time or money or space to experiment over and over until I find what works. I'm just hoping my first gamble pays off by carefully hedging my bets so to speak.

As you've mentioned in the past, you have access to "high-quality homemade compost from a neighbor" which you mineralized, but I don't remember if you said by what method. Did you add pottery clay, dolomite, muriate of potash and so on like the Aaron Talbot method, or did you just soak and dry it a few times? Just like "MTS" has been used (in this thread alone) to refer to both mineralized topsoil or Malaysian Trumpet Snails, the term "mineralized topsoil" seems to have several meanings as well.

At my local Home Depot and Lowes, the only "generic topsoil" that was available contained cow manure. The only options I could find that seemed like possibilities were MGOCPM and Scott's Premium Topsoil. I picked the MGOCPM because there seemed to be the most information regarding it's use. However, most of that information seems to not apply to what's available where I live because my bag was almost completely wood chips and tree bark. Perhaps it should have been labeled "fine mulch" rather than potting mix.
 

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According to the information in this thread (and the definition of the word itself) anaerobic conditions are caused by the absence of oxygen in the decomposition environment, not the presence of organics
I'll break down your statement further

absence of oxygen in the decomposition environment
Your statement is quite contradictory. When you say decomposition enviroment please note that this means where organics are present ;) So the presence of organics is the reason there is decomposition enviroment and aerobic and anaerobic bacteria to go along with it depending on the presence/absence of oxygen.

To explain my point in my previous post, organics is fish poop, fish food, dead plants, dead roots, dead fish, etc..These accumulate over time in any substrate, filling the gaps where previously water used to flow in and out carrying that important thing called oxygen which aerobic bacteria uses...If one doesn't have enough plant roots to transport oxygen in such a substrate and prevent it from going anaerobic, then one siphons it to remove as much of that "mulm" as possible to make the substrate "breathe" again. Otherwise it will become anaerobic overtime.
 
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