transparent slime on my driftwood

It is a fungus which grows from within the wood. There are dozens of species of fungus, most are harmless, but some are toxic. Without examination by a microbiologist it is impossible to discern the species so we cannot know.

Fortunately most is harmless. I have had the toxic fungus on wood I purchased from a fish store, and I think it was grapewood which is well known for this toxic fungus.

 

If it is a harmless fungus, then you could just leave it. Or you could use a soft-bristle brush (something like a toothbrush) under running water (from the tap) to remove it. Do not soak the wood in any substance (bleach, hydrogen peroxide, whatever) because wood absorbs any liquid it comes into contact with and it is impossible to effectively remove any of these so the wood is then useless in an aquarium. These substances can leech out weeks, months later.

Some fish such at loricariids (pleco, whiptail, farlowella, etc) sometimes eat this, as do otos, and snails will eat it fairly readily.

If it is the toxic fungus, the wood needs to be removed and discarded. But, there is no way to ascertain whether this is or is not toxic, other than by a microbiologist. If fish weree in the tank, they would react to the toxic fungus quite rapidly, at least in my experience, with increased respiration, lethargy, and death. I am not saying this is what you have, and top be honest it most likely is harmless. If the wood is chunky as opposed to branching, this seems the harmless fungus.

 

This is not surprising as the fungus originates within the chunk of wood. Boiling wood is not advisable because this weakens the fibre and the wood is more likely to rot sooner, and that can be another issue.

Is the tank water remaining clear with the wood, or does it begin to get cloudy or hazy at all? When I had the toxic fungus on the branch, the tank water started to get cloudy which was what first drew it to my attention, and then I saw the fish respiration was very high.

 

The bacteria/cycling could explain the cloudiness. There is a good chance the fungus is not toxic, but there is no way to know without a microbiologist examining it, or seeing the effects should they occur. Given that many have fungus on wood and no issues with fish it may be the same here.

 

Probably logical, but I would not say with certainty.

 

While you all are talking about driftwood, I'd like to ask a question? Do you ever use limbs/ wood on your aquarium? I have a plecotomus who needs wood to chew on. Ever use a branch, and what kind of wood is good?

 

Welcome to TFF. As you are a new member, I'll just suggest that it is generally better to initiate your own (new) thread when the subject is not directly related. This allows for more members to see your post, which means more will respond.

As I'm here, I will answer...yes, natural wood is useful and as here necessary. You can buy various types of real wood in fish stores; my particular favourite is Malaysian Driftwood which is very dark brown, heavy so it sinks without having to be soaked/waterlogged, and being natural every piece is different. It is especially good for loricariids as some chunks have tunnels which these fish like.

You can also collect natural branches. Make sure the site is safe--free of any chemicals, pesticides, fertilizers, etc, either in your own yard or a woods/forest. Hard wood is usually safe, wood such as beech and oak. Make sure it is completely dead and dry, so always pick it off the ground. Break off an end to check the dryness. Then rinse it well; I tend to leave it outside in the rain and then dryer weather.