I have posted a question in my betta source forum and they think this has to do with my Dwarf frogs and not Betta so my question in that forum was

I have 13 gallons tank my husband got me for my early birthday with one betta fish and two dwarf frogs. I have this since Saturday and I noticed slime clear goo thing on top of the heater, what is that?Name:  image.jpg
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