Driftwood question

[TheRudeDevil]

So far I've been using bought driftwood for my different tanks (15g - 58g).
But since I'm getting a larger tank (120g) this week and going to set it up with some driftwood it wouldn't really do it to move the small ones from my old tank into the twice as large one.
Instead I was thinking of grabbing some of the roots that have been lying above ground on a pile of other trunks and branches for the past four years atleast.
It has been exposed of sun, rain, snow, winds and temperatures between -31°F and +100°F wich have resulted in the bark being almost peeled off completeley, which made it a bit hard to determine what sort of tree it is. It's most likely to be an european birch cherry but there is a slight chance it can be some kind of populus though.
I'm planning to let it soak quite some time before getting fishes into the tank in case of it leaking tannins or anything else into the water.

So my question is, how do I check the water for any tannins (or other toxins), except putting fishes into the tank and waiting to se if they die or not?

Haven't really been in a situation where to check for tannins before, got plenty of other water tests lying around though

 

[SpeshulEd]

Tannins aren't toxic, in fact they're good for fish.

Your best bet is to boil it to make sure there are no parasites in the wood.

 

[TheRudeDevil]

I thought about boiling it, but the size of it makes it almost impossible to fit into any pot. Was thinking of giving it a rather big dose of salt while soaking it though.
I could cut it up in smaller pieces and put it back together after boiling it, but I'm not very keen on trying to get it to stick together nicely afterwards.

 

[Chromobotia]

Boiling it is a good idea as suggested above. You can tell if it is leaching a lot of tannins by how it affects your PH. Driftwood when leaching will lower the PH. It will also discolor the water.

 

[TheRudeDevil]

I guess I can sneak over to the school on the other side of the road and borrow their kitchen, quite big pots in there

Or I can get a big bin and pour boiling water over it for an hour or two

I read up a bit on tannin acids. (Somewhat different information on different places, but the following was similar on all of them)

I found out that they use tannin acids for curing or preventing some disease on fish farms, and that tannin itself isn't dangerous to fishes at low levels. But if the tannin levels are too high it might stress the fish which makes it more vulnerable to parasites and infections. If a fish has a skin lesion it will heal very very slowly (or not at all) if there is tannins in the water.

Some plants got high levels of tannin acids in their leaves to prevent animals from eating them, this works since they taste very bitter (for humans atleast and apparently land animals).
Not sure that fishes got the same sense of taste as us, but I'd rather not swim around in something that tasted very bitter

 

[yengkypluto]

you could just put it in your bath tub and pour boiling water over it. it might take a while though

 

[TheRudeDevil]

you could just put it in your bath tub and pour boiling water over it. it might take a while though

The people that lived in this apartment before me got rid of the tub

 

[SpeshulEd]

I really don't think you have to worry about the tannins. Many of the pbass keepers on this site use peat moss and oak leaves to raise the amount of tannins in the water.

You got your information from this site:
http://www.aquascapesdesigns.com/tannins.html

Please realize they're talking about a TON of tannins leaching into standing water. They talk about black water in the amazon and use the excuse that fish can stand it because of the constant rain fall...and then remind you that you are mother nature when it comes to your pond.

In your tank, you shouldn't have standing water. You will be replacing the water in your tank weekly with water changes. The same as rainfall in the amazon.