Time to reinvestigate sand/EE - new active/cycled substrate research

[JediMasterThrash]

The problem is that both coco-fiber based substrates and sand are initially sterile. Also, some people have issues with sand being silica-based (possible dangers if regularly inhaled by human lungs, though this isn't an issue for crabs).Bacteria and microbes form when the substrate is moist, and these readily break down poo and discarded food. So I've assumed these are beneficial in the past. However, I really have no idea how to measure their levels. Also, as they break down poo, they likely release ammonia. How are those levels?Also, what is the pH of the soil, and what should it be? Cocofiber lowers pH, while lime or calcium-based sand increases pH.I think the answer lies down one of two paths:1. Creating a proper "Beach" substrate.2. Creating a proper "marsh/jungle" substrate.The idea is that we should create active substrates with a proper mix of bacteria, microbes, bugs, etc, to keep everything in balance. We probably need to start out with an infusion of small amount of natural balanced substrate, either active reef substrate, or natural leaes/litter from clean wooded areas.Then we need a substrate which will become naturally cycled and maintain this balance.If successful, we should have healthier crabitats that can go for years without a deepclean, and should be healthier for digging, molting crabs.1. For a proper beach substrate, I assume something made for reef-tanks would be appropriate. Like aragonite. There was also a thread on CSJ about micro-sized gravel (apparently what Carol of Crabworks and her 37 year old crabs use), though it looks like it's not available anymore.2. For a proper moist jungle substrate, I found this site for amphibian vivariums:http://www.livingunderworld.org/amphibi ... 0021.shtml It recommends using decaying leaf litter or activated substrate from an aquarium or natural pond to introduce a colony of beneficial bacteria. Bark or coconut husk chunks in the soil can help with aeration. Most of what I've read says to keep the soil well moist to keep the beneficial bacteria colonies to decompose surface matter. If matter isn't properly decomposed, it can become toxic.It needs aeration because anaerobic bacteria can be harmful. This page seems to indicate that having larger chunks of matte in the substrate helps with aeration. Probably because they help trap air pockets, and help push stuff around more when they dig in it. With the amount of tunneling and digging that hermit crabs do, I'm not sure I'm too worried about aeration.I want to experiment with a natural substrate in my next crabitat iteration in a few months. So I need all the input and suggestions I can get. And also to find on-line places I can order everything. Is there anywhere on-line you can order safe leaf-litter?Here's one recipe that might be worth trying:2 parts inert sand. 1 part ground coconut husk fiber (expanded, see below). 1/4 - 1/2 part fully composted leaf litter. 1-2 cups of substrate from an established aquarium or natural pond.http://www.livingunderworld.org/amphibi ... 0020.shtml It suggests ammonia buildup only happens in pooling water. So you need to avoid oversaturating the substrate such that water can start to collect at the bottom. It's probably best to get the sand moist at the start, and then only add water or mist as necessary to keep it moist and the humidity right, but not too much as to oversaturate it. It also reiterates that sterile substrates can be harmful to animals because there are no beneficial bacteria to break down matter or overwhelm harmful bacteria. I think it's very important that we somehow find an easy way to create a cycled substrate for hermit crabs.

[Willow]

I've been wondering about leaf litter myself. i've been wanting to throw some in, but I can't decide. I mean, if I grab a handful from under the snow in my yard, is it safe? I don't spray, but what if the neighbors do? And I live next to the park---I don't think they spray, because I've never seen warning signs (wouldn't a city park need to put up signs after spraying?), but maybe they do. Anyway.Do you think a few handfuls of used substrate from an established crabitat would do it for "cycling"? I'd hate to throw any gravel (from the fish tank) in there, gravel in the crabitat bugs me. Maybe put it in a nylon stocking, like some people do for cycling aquariums?

[Jedediah]

I use coconut fibre for the main part of the tank and playsand for a smaller beach area. The coconut fibre was mixed with a few handful or forest soil (well, cemetery soil, from an area with no graves and a group of beech trees) and I threw in some moss and leaf litter. This brought in springtails, booklice and I don't know how many other microorganisms who keep the tank very clean. I rarely see crab poop, food dragged out of the food dish usually disappears fast and when I throw in some more leaves and moss, it's gone after a few weeks. My crabs killed their bromeliad a while ago and it's gone now, I never took out the dead plant, it was just eaten away. All my rainforest terrariums work like that. I have never deep cleaned any of them since I set them up abut 5 years ago, except for the glass and water chages. I know a poison arrow frog keeper who has enclosures that haven't been cleaned for 10, 15 years, he uses tropical woodlice (who live mainly underground) in addition to springtails ect. This method of creating active substrates is very common with German herpers, usually the enclosure is set up, "inoculated" with forest soil and then left to itself.I like the idea of the larger pieces of substrate, it sounds logical to me. I would love to have earthworms in my crabitat to areate the substrate, but I haven't found an available species that can stand the warmth of the crabitat, all native species like it cooler.

[JediMasterThrash]

For a while several months ago, I had been suggesting that we should recycle some of our substrate during a deep clean to re-use as-is in our new tank to infuse what beneficial bacteria/microbe colonies existed in the previous tank. (i.e., don't bake it).However, Sue from Coenobita Research thought that my above statement, as well as using dirt or compost, were potentially bad ideas for a variety of reasons, some of which (But not all) seem to not have the same concerns/warnings as the website I linked above.Sue's arguments were (pardon me of I incorrectly represent something, but I'll do my best) that we have no way of knowing what the bacteria colonies are, and the ratio of beneficial to lethal. Baking the substrate would kill off most, but not all, which might keep it in check (but to mee seems like it might defeat the purpose). Also, proper fluctuations of heat, light, and humidity promote bacteria diversity. Without this diversity, there's no way to ensure that we keep the bad bacteria in check. Soil/compost isn't good because it's in a constant source of decay, and we can't control it well enough in our small environments.My crabitat has naturally had diversity, expecially with my latest iteration. I have timed UV lights for day/night fluctionations, and timed bonus 50w moon-glos to provide temp and humidity daily fluctuations to more closely model real life. I have good air cirulation with two tropicaire humidifiers. And I'm not worried about substrate aeration due to the contant digging and tunneling of the crabs.Also, by having mostly inert substrates such as sand or coco-fiber, and only a small amount of compost, would this keep any decaying process from the compost in check?There's also one other catch. What do we recommend for smaller, newbie crabitats? Assuming they have more trouble with keeping temp and humidity in check, and might not have any air circulation or day/night cycles, what is best?1. A sterile substrate that grows "hopefully beneficial" colonies in moisture. This is currently what I and most crabbers are doing. It breaks down matter extremely well, and theres good success with molting. However, I still feel I could be doing better, as my crab half-lives are still in the 2-5 year span, and I'd much rather have 20-30 years.2. A sterile but dry substrate (Sue also said that dry bacteria are usually safer). But I haven't found dry substrate to be effective at all in breaking down matter, and the website above said that old matter can become toxic if not broken down. Also, our crabs molt better in mosit substrate, and moist substrate is necessary to keep the humidity up. So unless you micromanage your crabs, I don't see how a dry terrarium can work.3. Active/cycled substrate, which potentially requires day/night cycles and aeration to work properly. How well can we create a safe and easy active substrate recipe for the general crabber?While I'm on the subject, I was also looking at water, and was wondering if there's any benefic to adding some aquarium chemicals to balance pH and ammonia to larger water pools?

[JediMasterThrash]

Jedediah, do you have any issues with the springtails or booklice getting out of the crabitat and into the house/other pets/house plants, etc?That's the only thing my wife has against me trying this out. She's afraid all the bugs will escape and create troubles in the house.There was one time I had flies breeding in the tank, and that didn't go over well...