If you have ever visited a fish message board like petfish.net Message Board, then you have probably seen questions about driftwood from time to time. In this article I hope to answer some of these questions, as well as put a few myth's to rest. If I can help to enlighten even one person then the time I spent compiling and writing this article was well worth it. As with everything in this hobby the information may or may not work for you or in your situation.
The most common question asked regarding drift wood is "I found this really cool piece of driftwood at the (insert wherever you found it) and I want to put it in my tank, how do I cure it?" No matter what method you decide to use, scrub your driftwood first. This will get rid of anything loose on it. There are quite a few answers to this question.
One way is to boil the piece for a few hours (I've seen some people say up to 8 hours) then to soak it until the piece rests on the bottom of the soaking container (Changing the water everyday or every couple of days at the most). Personally I like the boil/soak method, although this takes time so you need to be patient. Another way is to soak it in a bleach/water mixture (1 cup bleach/5 gallons water) for a few days. Of course bleach is poison, so if you are a kid get an adults help to do this with proper protective equipment and ventilation. Consider rotating the piece around occasionally in the bleach, as it seems to be more effective. Then rinsing it for a few days, by soaking it (Again changing the water daily). I would NOT recommend the bleach/water thing, as I don't like to take the chance that the bleach wasn't rinsed out and therefore could get into the tank, possibly killing the fish (see my exception to this below). I've also seen a person suggest putting it in an oven on 200 degrees (F) for a few hours, thus killing any little bugs living in it. This idea also solves the bleach concern listed above. As a former firefighter, I would also tell you that this could cause the piece to start on fire, possibly even burning your house down if you don't watch it real carefully. If you use the oven idea please watch the oven at all times. Another suggestion is to just weight the piece down and throw it in the tank.
The next most common question goes something like this "I put some driftwood I found into my tank and now the water is turning brown, what is it" The brown is the tannic acid leaching out of the piece into the water. Some people like this because it gives them a "black water effect". The leaching can continue for months or years after you introduce the piece to your tank. Another reason I like the boil/soak method listed in the last question is I think it helps to decrease the amount of tannic acid that leaches out once the piece is in the tank. One other way to reduce this "black water effect" is to do more frequent/larger (percentage) water changes. It has also been noted that the tannic acid can lower the ph in your tank. If you are concerned about this, then keep an eye on your ph level with regular testing. Another suggestion is to find a piece that has been "weathered", supposedly the piece will contain less tannic acid, as it will have already leached out during the "weathering" process. You can also add another carbon cartridge to your filter system to help clear up the staining. Remember to change your carbon cartridge more often if you have a very active leaching piece
After the questions listed above there are many different ones that pop up from time to time. Some of those are listed here.
"I found a piece of pine and want to use that. Is that ok?" The answer is NO. You should only use hardwoods (oak, maple, ash, elm or hickory) for your aquarium. The sap and pitch in the softwoods can and most likely will create a syrupy mess in your tank. The soft woods will also decay easier than a hardwood. If you have a difficult time telling which type you have I suggest you use the following method. After the piece is dry, take the edge of your fingernail and depress it in to the piece. If it goes in easy then you have softwood. Get yourself another piece.
"I soaked my driftwood for months and it still won't sink to the bottom of the tank." Fortunately there are a few ways to make it sink. One way is to use some fishing line and tie a plant to it for added weight (and beauty). Or you could silicone (make sure you use an aquarium safe silicone) it to a piece of slate (if you like the look) or to some flat pieces of plastic (then bury the plastic in your substrate). Some people have used titanium or stainless steel lag bolts imbedded in the wood to weight it down. I would not do this, as I don't want anything metal introduced into my tanks. I also heard of one person that drilled some holes in the bottom of a piece then filled it with molten lead to make it sink. You could then silicone over the lead to seal it from the water.
"I read (heard) that driftwood is good for my plecostomus. Why?" From my research this is true. It seems that pleco's rasp fibers off the wood and break it down for the cellulose. As I understand it, it helps their digestive system. I guess it is similar to fiber in a humans diet. Unfortunately I have found very little information on the internet regarding this.
"Can you use driftwood from saltwater for a fresh water tank?" Yes, you can use driftwood from the ocean for a freshwater tank. Remember that exception I mentioned before? Here it is, for a piece from the ocean I would use the bleach/water mixture just to be sure that nothing bad got into my tank. While I have no experience with this, that would be what I would do.