Generally it is not a problem. There is a spray to help prevent the growth, but I can't remember the name, the local garden store may know the name.
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BlueBear Reviewed by BlueBear on . Is green algae harmful in top of rockwool? (bonzai 240) If I grow in a bonzai (rotary garden) and the tops are solid green, will that cause any problems? I covered with reflective tape. This may be a stupid question. Is there any way that the glue from the tape could cause any damage to the plants? Next time I will be ready and have pre-cut mylar to fit over the top from the beginning. I only have the machine 1/3 full but so far they look great. Half were clones and half seeds. I topped the clones and they all look great. This is only my Rating: 5