Adding driftwood to your freshwater aquarium can make a perfect decorative element that brings your waterscape to life. But, you can’t just add any old piece of wood you find on the beach or lying in the forest the moment you bring it home. You have to prepare it first.
The best method is by boiling it in water as you would a cup of tea.
This is because wood comprises a compound called tannic acid, known as tannins. This provides trees with a defense mechanism against things like bacterial infections, pest infestations, and fungal growths. Unfortunately, it can cause problems in a home aquarium.
Are wood tannins bad for fish?
Wood tannins are often terrible for most fish because these act as defensive compounds against bacteria and fungi that most fish require to thrive. If it doesn’t kill the fish, it will make them very sick and it lowers their immunity.
For instance, there are a few rivers in the Amazon stained dark brown, also known as “blackwater,” because of the high concentration of tannins. Very few species are able to survive in this water and the fish that do are often easily susceptible to diseases.
Fish and Acidity
Also, driftwood tannins can acidify the water’s pH balance unless the water in your tank has a high buffering capacity. Changes in pH can be devastating for things like shrimp and some types of plants.
All that said, there are some species of fish, like cichlids and catfish, that thrive on a little acidity provided by driftwood tannins. So, it’s essential that you study up well on your particular fish and what’s its native habitat is like. Recreating its natural environment as best you can keep the fish happy and healthy.
How long to boil driftwood to remove tannins?
Removing tannins by boiling the driftwood can be a long and painstaking process. Many factors play into the length of time it takes to do this. The size of the wood, the type of wood, its age, and its dryness will determine whether it takes only a couple of hours or a matter of days.
There are two main methods for which to prepare driftwood: soaking and boiling. Soaking will take much longer than boiling but either method can take a long time. Larger pieces of wood, wet or green wood, and young timbers will take a much longer time to prepare than old, small, and well-dried pieces.
What is the process of boiling driftwood to remove tannins?
First, clean off the wood to remove dirt and debris from the surface. Then, dry it in the sun, a windowsill, or some area where light and air are plentiful. Make sure it’s fully dried before you begin this process. This is because you want to avoid mold developing on the wood once introduced into the tank.
Then use a pot large enough to submerge the wood in water. Many people swear by lobster pots or large soup pots for boiling. Once the water gets to a violent roll, let it go for 15 minutes. Then, drain the water and repeat the process a second time.
After the second boil, drain the water and add more water again but only let this third boil go for 10 minutes. Allow this to cool and then remove the driftwood.
If you notice the water is still a dark brown after the third boil, it means not all the tannins are out of it. You have to let the driftwood dry and try it again and you’ll have to repeat this process until the water is clear.
If this seems too tedious for you, you can always soak the piece of driftwood in a bucket of water. Change the water out when you notice saturation of the tea-brown color. Leave it to soak until the water no longer turns brown.
Whether boiling or soaking, make sure you use reverse osmosis or filtered water and don’t use it directly from the tap. This will ensure the wood stays clean and free of mold when it finally does go into the tank.
Are there any other methods to remove tannins from wood?
If your piece of driftwood is too large to fit into a pot, you can try to use a potato brush and hot water to scrub the surface of the wood. But this may be even longer than boiling it.
Boiling or scrubbing driftwood is the only way to loosen its tannins. But, if you’re going for the soaking option, you could include some activated charcoal into the water while it soaks. You’ll switch this out along with each change of water.
Of course, the best way to acquire a tannin-free piece of driftwood is to buy it from a pet or aquarium store. But ensure you avoid getting the wood intended for lizards as these are chemically treated and can harm your aquatic life.
How do you get driftwood tannins out of water?
If tannins end up in your aquarium water even after cleaning it, you can use activated carbon granules to control it. Most filters that contain activated carbon can usually take care of excess tannins that creep in from driftwood.
Ensure the activated carbon you get is chemical and heat-treated for aquariums. This will guarantee that it’s nice and porous. It will clear up the tea-stained color in no time because the activated charcoal binds up all the tannins. If tannins are a constant, replace the filter as much as needed until the filter stops clarifying the water.
How do you keep driftwood from turning the water brown?
Along with using activated carbon, do partial water changes to control the brown water emanating from the driftwood. But make sure this isn’t going to hurt your plants or fish with such frequency. For instance, freshwater shrimp cannot tolerate frequent changes of water because of how it shifts water conditions.