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What's Growing in my Vivarium?

Seemingly on a daily basis, I receive a phone call or email from a new frog keeper who has discovered some unknown organism in their vivarium. These alien organisms often spark fear or worry. Are they harmful? Will they hurt my frogs or kill my plants? What is it? Here, I'll post photos of different unidentified organisms and try to shed some light on what they are, what they do, and the like. Remember, in general fungus is beneficial for your tank. It helps keep things cleaner by breaking down waste into nutrients plants can use, and often even helps plants grow better! In fact, we designed and created Josh's Frogs Bioactive Booster to introduce beneficial fungus into your tank and help it stabilize faster.


What is it?Some kind of neat bracket fungus, a close relative of the mushroom. Is it harmful?Only if you're allergic to awesome! Bracket fungus are quite uncommon in vivaria, as they seem to require decent airflow to thrive. Consider yourself lucky, and enjoy it while it lasts! Like many fungi in the vivarium, they'll only be visible for a brief time before disappearing, sometimes never to be seen again. Springtails or Isopods in the vivarium will earnestly consume fungi.  mushroom.jpg What is it?It's a mushroom, and a brightly colored one at that! What you're seeing is the fruiting body of the mushroom - the vast majority of the organism is called the mycelium, which looks like roots and is probably spread throughout the piece of wood the mushroom is on, deriving nutrients from the wood as it decomposes. Is it harmful?Only if you're a piece of wood. Mushrooms and fungi will cause wood in a vivarium to break down a bit more quickly, but that's part of nature. Mushrooms will not harm your frogs or plants, and actually can contribute to a cleaner and healthier vivarium. Enjoy it while you can - mushrooms typically only last a day or two.  photo-1.JPG What is it?The powdery white growth appears to be a variety of mold (sometimes called mildew). Mold likes to grow on wet, nutrient rich surfaces. Is it harmful?Mold will not harm your plants or frogs, and is a completely normal part of the cycling process of a new vivarium. In the first 6 months or so, expect to see lots of mold. Mold comes in many different colors - the most common are white or green. Springtails and Isopods will make short work of any mold.  slime_mold.jpg What is it?An alien. Kill it with fire. No, just kidding! This is a slime mold. Slime molds are pretty uncommon in vivaria, but will randomly pop up from time to time. In the years I've been working with vivaria, I've only seen a handful of slime molds crop up. Slime molds are not a true fungus, but they serve many of the same purposes in a vivarium. The slime mold pictured is actually a colony of several thousand normally single celled organisms that come together when food is scarce. Is it harmful?Slime molds are completely harmless, although their appearance in a vivarium can seem quite startling. Like mushrooms, they are often gone very shortly after they are first seen.  mushrooms.jpg What is it?Yet another variety of mushroom. This one may not be as colorful as the orange one shown previously, but it makes up for it's pale complexion with numbers! When this mushroom appeared in a vivarium, several hundred of them were visible. In a couple days, none could be seen. Is it harmful?Nope.  photo.JPG What is it?This appears to be an unusually colored blue mold. Is it harmful?I wouldn't recommend breathing it in, but it will not harm your plants or frogs. Springtails or Isopods will make short work of it.

Is your frog tank being invaded by aliens? Have something in your vivarium that needs to be identified? Email us a picture at [email protected], and let us identify it for you! If it's cool or unique enough, your photo may even end up here!

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