How to Propagate Marimo Balls
There are many god reasons to propagate Marimo balls. For one they are a great addition to any aquarium, and secondly, they can be very good for stress relief.
After you have had your Marimo balls floaing around for a little while, you just might notice that some of the bigger Marimo balls are slowly growing lumps. These lumps are actually a smaller Marimo ball forming within the larger one. These lumps growing on the larger Marimo balls will slowly work their way out of the larger Marimo ball to become their own. This might leave a big hole in the larger Marimo ball, but that is nothing to worry about, as this is a natural process and is perfectly healthy.
One of the easiest ways to propagate Marimo balls is to literally just take them apart, exposing all of the individual algae strings. The strings in the center of the Marimo ball are inert until they are exposed to light. These strings have the uncanny ability to rejuvenate within four to six hours of coming in contact with any source of light. The best part is, is that Marimo balls in their natural habitat will just naturally break apart as they get larger, so you don't need to get involved in the propagation process if you don't want to. Some people don't like to get involved because they are afraid of getting the green algae under their nails.
However, the most difficult part of the propagation of Marimo balls is rolling the individual strings back into a ball. The process of gently rolling the strings in the palm of your hand takes patience and a lot of time, you may not want to have a very full schedule if you decide to try and propgate Marimo balls. A better solution is to place the new Marimo ball into a round container such as a bucket, and add a gentle circular water movement. If all else fails, just attach the strings to a piece of driftwood or to stones and watch it form a natural carpet!
It should be noted that if you do opt to take the easy way out when it comes to the propagation of Marimo balls, that you will really be missing out on the zen like relationship you can have with your Marimo balls by getting more hands on.