| This cold front moving through the area may well kill fungal spores. Fungal spores do not live through the cold.
Physan 20 is a topical algaecide and I do not find it works very well on fungus. It has some effect as a weekly preventative, but not very effective as a cure.
You want to use a systemic fungicide that goes into the plant rather than a topical.
Phyton 27 is the most common available to hobbyist. It is expensive $40-50 for a small bottle but you use very little and it will last your lifetime. Cleary3336 is a commercial fungicide that is cheaper and very effective but may not be easy to find. Subdue is very good and the most expensive $224 a qt wholesale.
Others are Banrot, Thiomyl, Natriphene and Camelot.
If you have to use a topical use it several times a week. Dithane is cheap and found most everywhere.
As to the two you have I have never used them but go on the INTERNET to their web site and see if they are systemic. They probably are not. If not use them several times a week.
All these poisons are very dangerous so be very careful in their use.
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jerry  |