In an well fed tank rosette plants can get out of control and dominate the sediment. While these plants do a tremendous job of aerating the soil, which is an asset, they can become obnoxious as they spread causing plant clones to appear at unexpected or unwanted locations. I've pulled up crypts to find they have had 3 foot long roots. When planted in the sediment, roots grow very fine hairs which make contact with the sediment particles. It is via these hairs via electrochemical action the nutrients in their ionic forms find their way from the sediment to the plant. In a way this can be thought of as being "plugged in" to the sediment. When you uproot a plant you are breaking this connection with the sediment. When replanted, it takes time for the hairs to grow again and for the plant to optimize it's root feeding infrastructure, however, assuming the water dosing and CO2 are adequate, it's a minor setback and the plants will shortly resume as if nothing happened. This is indeed a good way to control the spread and dominance of these plants. You can use the opportunity to cut the rootball back to within a few inches as well as to separate plant sections thereby propagating or selling/donating spare plantlets, and at the same time keeping the biomass thinned and under control. This helps maintain good flow and distribution. If you have a lot of these plant typesin the tank just do sections at a time a few times a year depending on growth rates.
Cheers,
