If its fungus, then you'll want some type of antifungal medication to get rid of it. This might affect the plants though. When you remove it all, how fast does it return? Jungle brand makes an antifungal medication. You could try that.
Are you adding anything to the tank, like fertilzers or anything? Any fish yet? Are you adding any food?
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*Kristin*
5 Planted tanks:
55g, 40g, 29g, 10g, 5.5g
10g N. multifasciatus tank, 5.5g Platy fry
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