This is kinda re-visiting an old topic that I had kinda let drop a while back but some question
that Hadn't really gotten answered have started niggling me again.This is wondering about using wood chips as media again. I started googlebutting around to see if I could find anything stating that particular wood types are toxic to particular or any fish.
What I've come up with is that most conifers (at least fresh) are not likely to be a good idea in aquariums. Boiled driftwood seems to be the best choice though it can leach tannins which might be unappealing to some people though they might be fine for many types of fish.
I learned that many fish need wood in their natural habitat!
Treated woods and creasote are bad for fish.
There is lots about fish eating wood debris from wood pulping plants and paper mills but it didn't seem clear how bad this was in some of the reports.
So, back to the issue of cypress. When I had asked about it, I was told not to use it in a system with fish but when I asked why, I was told that there are chemicals in it that will inhibit plant growth. I wasn't worried about the plants really since I had been using cypress mulch as media in Hydroponics systems and know of many other people who have done the same here in the SE USA. (This might all be because the cypress growing in swamps here is very different from cypress growing in AU.) Can anyone shed new light on this one?
Anyway, I wouldn't use cypress mulch now anyway as it isn't being very sustainably harvested as far as we can tell. This question is more of an academic question now.
What about other wood chips? (provided they are not treated with anything!) Anyone know of a reason not to use say Oak?
Here is the main reason I suspect that most people would want to stay away from most wood materials is that they will tend to leach tannins that will bring the pH down. What if bringing the pH down would actually be a good thing?
What sort of benefits/drawbacks do people see with what wood might leach into a system. I expect there may be some benefit in nutrients leached with the tannins and for fish that like blackwater it would probably be nice. What other points do people see and what types of wood might be good and what others might be bad?
I could get lots of nice big driftwood chunks from the place up in Michigan, most of it is quite old.
Tannins, sap, whatever else leached out and was obviously toxic to the tadpoles.
