From the Aquatic Plant Q&A at the Krib:"How do I disinfect my plants?''
New plants may have unwanted hitchers: snails, algae or disease. Disinfection can help reduce their transmission into the tank, and can be used to remove algae growths from established plants. Beware, there is always a danger of going too far and damaging the plant itself. Some popular methods:
- A ten minute soak in potassium permangenate (pale purple) works well; it is available in dilute form from Jungle products as "Clear Water". Permangenate is particularly good for killing bacteria and pathogens.
- A 2-day soak in 1 tbsp/gallon of alum (buy it at drug stores) is good for killing snails and their eggs.
- If the plants are kept in a fish-free system for three weeks, parasites like ich and velvet will die without their fish hosts.
- A soak in a 1:19 diluted bleach solution; 2 minutes for stem plants, 3 minutes for tougher plants. Make sure to remove all traces of bleach afterwards by rinsing with water and dechlorinator. This method can kill your plants, so use only as a last resort against hell...o algae.
Edit October 13, 2007:In my experience Potassium Permangnate is great as a disinfectant dip both for plants and nets. It kills algae a bit safer that Bleach as far are being as hard on tender plants and mosses that occurs with a bleach dip. It also is pretty effective in killing unwanted bacteria, fungus, and other potentially harmful organisms. Note that potassium permanganate will stain clothes, carpeting, hands, etc. so take those precautions. It is also a powerful oxidizer so safety glasses should always be worn when working with it. Also note that regular dechlorinator (sodium thiosulfate) will neutralize potassium permanganate too.
To kill snails and snail eggs on plants the most effective method IME, is using an alum bath...not a dip, but a bath. For snails and snails eggs a 2-3 hour soak in a solution of 3 tablespoons per gallon of water is a better choice. Alum isn't nearly as effective as bleach or potassium permanganate for killing algae though. Alum is aluminum sulfate and Alum USP can be obtained from a compounding pharmacy or grocery stores. (It's usually with the spices, herbs and pickling supplies).
