These are most likly planaria. This is a harmless copepod and it occurs when conditions are right in the tank. To eradicate them, thoroughly and I do mean THOROUGHLY, vacuum the gravel, wash the decor, including plastic plants, with very hot water, and do a 33% water change. Remove the filtration system, wash it well with hot water, and replace all the media. Using a paper towel, wipe the inside of the glass, and along the edge of the top of the tank. Also, using a paper towel, thoroughlly clean your hood and light fixture with hot water. By hot water, I do not mean boiling, but definitely as hot as you can stand it from the tap. Refill your tank with fresh water and water conditioner. Wait 24 hours, and do a second water change with gravel vacuuming, but if you were thorough the first time, you should not need to clean the filter, hood, etc, again. You might want to place resin or ceramic decorations in a sunny spot in the house for the 24 hours between water changes.
In most cases, this cleaning will take care of the planaria. To prevent it from coming back, establish a routine of vacuuming and changing 25% of the water weekly. Also, if you have deep gravel, remove some of it, so it is no more than 1.5" deep. This will make vacuuming much, much easier, and help prevent a flare up again.
answered 1 year, 11 months ago
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