One last stupid question - potting soil

mwh9

Arachnoknight
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I have read that it's ok to use potting soil, but most of it has basic fertilizer in it, nitrogen, potash, and potassium. Should it be avoided?
 

mitchell123

Arachnoknight
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Don't use potting soil ,you will regret it in the end .Due too alot of fungus problems that could result in that your T could die.
 

Aurelia

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shouldn't it be ok if you bake or freeze it? I use potting soil and my Ts are just fine. I guess I wouldn't recommend it for more tropical species who need a lot of moisture though. I was told (by someone on here) that nitrogen, potassium, and potash are ok. It hasn't hurt my spiders at all for the past 6 months that I've owned them.
 

Talkenlate04

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shouldn't it be ok if you bake or freeze it?
Baking and or freezing it is not going to remove any fertilizer that may be in some potting soils. I just avoid it cause like some others have mentioned I had more mite and mold problems with potting soil.
 
B

babylon5girl

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my problem with it is the fungus and mold my t's were never bothered by what was in it. Ive switched to eco-earth.

good luck:D
 

Brian S

ArachnoGod
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I dont like potting soil especially for tropical spp because it doesnt hold moisture near as good as peat or coconut
 

Mallard

Arachnoknight
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I researched potting soil as a cheap Alternative to other substrates. Everybody who says dont use it is right. Most contain fertilizer some even contain pesticides. The consequences of that are obvious.
There are many post with solid recommendations of substrate. There are several types formulated for inverts.
Jason
 

Aurelia

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Baking and or freezing it is not going to remove any fertilizer that may be in some potting soils. I just avoid it cause like some others have mentioned I had more mite and mold problems with potting soil.
I was talking about killing any fungus that might be in it, not fertilizer.
 

JMoran1097

Arachnoangel
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just use eco-earth coconut fiber substrate. in fact, if you look around, a lot of independent pet stores carry it in bulk for like 10 bucks per 10 pounds.
 

Stan Schultz

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I have read that it's ok to use potting soil, but most of it has basic fertilizer in it, nitrogen, potash, and potassium. Should it be avoided?
Congratulations! You've just started this summer's first major flame war! :D

Here's the low-down on potting soil:

Potting soil used to be just peat (aka Canadian peat, peat moss, black peat) with a little perlite (a baked mineral, little white, crisp balls) or vermiculite (aka horticultural vermiculite) mixed in for color.

Now, because of the escalating cost of peat and due to marketing pressures they're adding composted lumber industry byproducts (aka rotten sawdust), fertilizers and reportedly in some cases, insecticides. Remember, that the potting soil manufacturers are marketing to the house plant growing hobby and industry. They couldn't care less about arachnoculture, and many of them would rather all the spiders in the world would disappear this afternoon, being confirmed arachnophobes.

We are concerned that at least some of the lumber byproducts may contain pine and/or cedar (aka red cedar, juniper) and therefore are probably unsafe for arachnids. No one's absolutely sure at this point partly because we haven't enough experience with the stuff and partly because we don't know what effect the composting process has on the toxins. So far, we're taking the conservative approach and saying "DON'T USE IT!"

Similarly, we strongly suspect that the added fertilizers may be dangerous. But again, no one has yet proven it. On a fundamental, molecular level, such fertilizers are merely nitrate, phosphate and potassium salts of some sort or another. These occur naturally in many soils around our planet and the tarantulas living in those soils apparently do quite nicely in spite of them. What we don't know is the "some sort or another" part, i.e., what are these salts complexed with to make them more soluble or to give them other properties. Are those phantom additives, if they even exist, harmful to our arachnids? Is the concentration of the fertilizer important? We have little clue. So far, we're taking the conservative approach and saying "DON'T USE IT!" here, too.

What about the insecticide part? If some potting soils are really being loaded with these we have a huge problem. Without question insecticides at any measurable concentration are bad for our arachnids. If the package advertises or even merely lists insecticides or "insecticidal properties" on the label, avoid it like the plague!

A major question here is whether or not the potting soil was accidentally doped with pesticides while being transported or stored. (Just about any sort of handling or vibration could easily raise aerosols or dusts that could contaminate otherwise safe potting soil.) Or merely by being stored next to pesticides on a store shelf? We can't tell. It's one of the chances we take.

So, if you really Really REALLY want to use potting soil, buy plain peat instead. It won't cost as much and it'll do the same job. (It's readily available in various sized bales at just about any large gardening supply for only a few dollars.)

We often hear people complaining about mushrooms, molds, and other fungi growing on peat (hereinafter read this to mean "peat or potting soil"). This only happens if you keep the peat damp. Fungi find life almost impossible on dry peat.

First, you need to assess why you're keeping the peat damp. If you think fungus gardens are "kewel," fine. If you think it needs to be damp to maintain a high relative humidity, you need to ask yourself the following two questions:

1. "Why do you think that your tarantula needs such a high humidity?"

2. "Why do you think that damp peat is the best way to produce such a high humidity?"

Lets discuss #1. We lived in Calgary, Alberta, Canada for over 20 years. Calgary has a very dry climate. In fact, especially in the depths of winter, it becomes so dry that stripping a polyester sweater off oneself in a darkened room is almost as spectacular as attending a New York Independence Day Celebration!

Calgary is also home to a truly amazing ethnic mix. We have people from all over the world, easily 6 of the 7 nominal continents living there. In spite of their native habitat (e.g., Sulawesi, the Ukraine, Uganda, Iraq, Hong Kong, Bogata, you name it) they mostly complain about the cold winters, almost never about the dryness. In fact, in spite of the cold and especially the dryness they seem to do just fine, going about their daily affairs, raising families, holding jobs, etc. Why? Because they adapt to it! Now what makes you think that tarantulas, that have evolved on this planet and have survived here for several orders of magnitude longer than humans, couldn't do the same?

The fact is that there are really very few tarantulas that can't adjust to a dry climate and a low humidity, at least as pets. The only ones I'm aware of are members of the genus Hystrerocrates, T. blondi and possibly T. apophysis (no personal experience here), members of the genus Ephebopus, and possibly one or two species from southeast Asia. (I've not kept a lot of the Asian species.)

So, why ARE you keeping your substrate damp? Probably because someone or some care sheet somewhere told you to. And the reason they tell you to is because their tarantulas managed to survive in spite of the oppressive humidity, not necessarily because they needed it!

How about question #2? Beats me! Maybe because it was the first strategy that came to mind. There are other ways of adjusting the relative humidity in a tarantula's cage.

How about one of those little ultrasonic foggers that you sometimes see in reptile cages? They work, but how much money do you want to spend on high tech gadgets instead of interesting tarantulas? And, are you really sure that the squeal from those things isn't driving your tarantula nuts? (You may not be able to hear it, but can they?)

Besides, there's a simpler way. Merely use a slightly larger water dish (or a second one) and cover the cage top with plastic food wrap. More water surface results in water evaporating into the cage more readily and the plastic covering prevents it from wafting away into the room air. You can keep the substrate dry (read that to mean "relatively mite and fungus free") and the air still relatively humid.

Now we come to the subject of coconut coir (aka "Shred-a-Beast" or something). This came on the market about the time that Marguerite and I were downsizing our collection in preparation for our retirement, so I'm no expert. But, a perusal of this and several other forums strongly suggests that if you keep it damp you'll run into the same problems as with damp peat: fungus gardens and mite infestations. Since it's an organically derived substance you could have predicted that. And, the solution is also the same as with peat. Keep it dry and find another way to maintain the desired humidity. Is it better than peat? Whatever you think! Ultimately it makes little difference because the tarantulas don't seem to be complaining.

I now have on my asbestos suit. Let the flame war begin! :D
 
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Stan Schultz

Arachnoprince
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shouldn't it be ok if you bake or freeze it? ...
Aurellia and All -

Baking, microwaving, freezing, bleaching... All of these methods of getting rid of the fungi are pretty much useless because bits of the fungus may still be left in the cage. And, heating the substrate will raise an immense stink that your family/spouse/roommate may hold a conflicting opinion about!

And, even if you go through great lengths to sanitize the cage (I heard of one lady who worked in a hospital who treated her cage with ethylene oxide to sterilize it!), more spores will settle out of the open air to reinfest the cage as soon as you turn your back. Tomorrow you'll see a little mushroom with a little banner "WE'RE BAAA-AAACK!" growing in the cage anyway.

As far as I know, drying the cage out and keeping it dry is the only way to get rid of it permanently. Sorry.

Edit: Actually, there's another hypothetical alternative: Spray the entire cage down with a methylene blue or gentian violet solution. These are both known to kill fungal mycelia, I just don't know what the long term effects would be on your tarantulas. Do you really want an intense blue or deep violet Chilean rose? (Sorry. I'm being silly!)
 

jen650s

Arachnobaron
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May 29, 2007
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I had never had a mold problem with peat or peat mixed with vermiculite moist, dry or any where in between. But about 6 weeks ago I started using Bed-a-Beast and have had mold and mildew problems in all but my very driest enclosures and am going back to peat. It's cheaper and seems to work better.
 

mwh9

Arachnoknight
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OK, sorry, I should have thought that this would cause some disagreements. For what it's worth, I got some of the coconut stuff today. I did decide to use a single layer of aquarium gravel over what ever I use in the bottom. This is so that no matter how moist the substrate is, the spider will not be sitting on wet ground. The tank height is only about 2 inches higher than her leg span, so a fall is not a real concern, besides, she does not do any climbing. And there it is, I probably started some thing again. Thanks for every one's input. All opinions are valued. That is what this is here for.
 

Stan Schultz

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OK, sorry, I should have thought that this would cause some disagreements. ...
Not necessarily disagreements. Just "discussions." And it's the best way for many of us to learn.

... I did decide to use a single layer of aquarium gravel over what ever I use in the bottom. ...
For years Marguerite and I kept literally hundreds of tarantulas on aquarium gravel and had virtually no problems with it. But there are two additional issues you need to know about before you make a decision about its use:

1. The gravel we used was usually "red flint" (well worn, river gravel) or sometimes various artificially colored gravels that were relatively round and smooth. Thus, we avoided rough or sharp gravel.

2. The only problem we had concerned one (and only one!) species: the curlyhair tarantula (Brachypelma albopilosum). A significant number of these developed a scab-like lesion on the bottoms of their abdomens (opisthosomas) that we suspected was due to being dragged over the gravel. Subsequently, we switched to using potting soil, and while the incidence of those lesions diminished, they still developed in a significant number of curlyhairs anyway.

Our conclusion was that, while the lesion wasn't necessarily caused by the gravel, gravel may have contributed to the cause.

An interesting side note is that the current revision of The Tarantula Keeper's Guide recommends the use of aquarium gravel. It was after the publication of the book that we, with accumulating evidence, decided to change our "party line" to recommending potting soil instead. Now that the potting soil sold in most stores is adulterated with lumber byproducts that may contain red cedar and other harmful additives, we are again changing our recommendations to urging the use of either pure peat because it's very inexpensive, or coconut coir (e.g., Bed-a-Beast®) even though it may be significantly more expensive. Either seems to work acceptably.

Apparently, the use of horticultural vermiculite is now falling out of favor, presumably because many tarantulas have some trouble accepting it. But for years it too was an important substrate, used by both enthusiasts and dealers alike, especially for baby tarantulas in pill bottles and mini deli cups.

At about the same time that we began recommending potting soil a contingent of tarantula keepers adopted the stance that aquarium gravel was unilaterally bad and potting soil (or something else) was good, thus the hue and cry was raised and now aquarium gravel has a bad reputation. I think that largely, the SMOOTH grained gravels are acceptable, and if you want to add a little color to your tarantula's cage the use of smooth gravel is okay. It's the sharp, crushed gravel that's bad.

This contention is supported to some degree by the fact that tarantulas in the wild live in soils that are often composed of mixtures and aggregates of many different substances, including a lot of sand and gravel. And, I have never seen any that I thought were injured by these soils, and I have never heard anyone else complain either.

Having said all this, I would suggest that you remove the aquarium gravel if it's rough, sharp or if you merely have doubts about it.

... This is so that no matter how moist the substrate is, the spider will not be sitting on wet ground. ...
A few days on moist substrate won't do any harm. It is long term dampness that may kill it. If the substrate is a little too damp when you first introduce the tarantula, merely hold off covering the cage top with plastic food wrap for a few days (assuming you're concerned about humidity or its lack in the first place).

I hope this clears up a few things.

Best of luck. Enjoy your tarantula!
 

mwh9

Arachnoknight
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Jul 25, 2007
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Thanks for you advice, I did use the smooth gravel for the very reason that you stated. Using crushed coral or any thing rough occurred to me as a bad idea. I do have to admit that some of the reason for using the gravel was because the T was not very visible on the coconut. I really don't know if I will continue to use the gravel but, did not notice any ill effects so far. Again thanks for the reply.
 

Orchidspider

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Jun 26, 2004
Messages
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Thanks to both you Schultz's for your thoughts

I love the book you both wrote and it has to be one of my favorites of all time, thanks for your comments. I like the coco fiber,but it gets mites just as easily as anything else thats kept damp. And your right, most of my t's do just fine in dryer conditions- cept my Blondi, and Tawny baboon.
 

R.W.

Arachnosquire
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Aug 19, 2007
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Question:

Can I put the peat moss straight into the tank out of the bag?
 

P. Novak

ArachnoGod
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Sep 12, 2005
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Question:

Can I put the peat moss straight into the tank out of the bag?
I can and have in the past, but it wouldn't hurt to stick in the oven for awhile to steralize it and kill all the nasties that might be living in there.
 
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