Did you know you could build a whole ecosystem in a jar?
Maynard Okereke walks you through building a terrarium—a sealed, self-sustaining ecosystem where you can witness the water cycle, photosynthesis, and plant life in action.
by TheMuseumOfScience
1 Comment
I kinda have a bone to pick with some of these vids. Squat jars with opaque/light blocking lids are just not good situations for terrarium plants, as even put in a sunny south window, they may never get enough light. They look nice, but provide little upwards growth potential for plants, and though they might make nice mossariums… I would still avoid it, and recommend people go with clear lidded containers like apothecary and candy jars instead.
similarly, the Activated charcoal/carbon in the drainage layer is… definitely something I’d not recommend. Activated carbon does not act long as a “Purifier”, and only stays activated for 2 weeks to 3 months. After that it is entirely deactivated and will rot within the drainage layer, letting out anything it has sucked into it back into the drainage layer to get reabsorbed into the soil above. You can easily test this out by getting a filter media sock and some activated carbon, rinsing it off, and then listening for the hissing sounds. Then leave it in a sealed jar with some water for a month. Guarantee when you pull it out a month later, it’s not hissing, and if it is, it’s very quiet. By 3 months, it should be absolutely silent, thus not doing anything. Anyone with aquariums should have expereinced this, especially since this nature of activated carbon depletion is why companies that sell you on filter cartridges want you to swap it with a new one at most every 3 months(this is a scam for an entirely different reason I will not go into here, though, but the basics is you only want to use charcoal after a medication round to remove it from the water, otherwise that space is better taken up by scrubbing media and biomax)
If you WANT to use it because you’d rather use tap water, I’d put it on top of the substrate barrier instead, preferrably on top of a fine layer of sphagnum moss that acts as a wick to move water up from the drainage area and into the soil. This positions it best for what you want it to do: Purification and filtering. But, if you’re not using tap water, and are using distilled, bottled, or RODI water to set up your terrarium, you can totally skip using activated carbon. It really doesn’t do anything for a long term terrarium. You want anything with the possibliity of decaying to be above your drainage layer, basically, so it gets churned into soil eventually. That’s why we use stones(Preferrably pumice or lava rock imo, but I have used aquarium rocks before too) and leca for the drainage layer. nothing else should be in there.
Horticultural charcoal is entirely a different thing, and from looking at what the guy actually added to the terrarium, it looks like he drops horticultural charcoal in, claiming it’s activated carbon… Horticultural charcoal should be mixed with the soil, and does not belong in the drainage layer. It is doing nothing in there, and definitely not purifying. What Horticultural charcoal is meant for is creating a less dense substrate, and with it’s larger pores it becomes a great living environment for springtails as well. It’s not been created in the same way that makes the “Hiss” sound that creates activated carbon and makes it draw water impurities into it, so it does not filter anything. You might as well be dropping fine bark chips into the drainage layer when you do this, because it’s almost the same thing.