White stuff around my bettas mouth

[Algidmaze]

My blue Vail tale betta male has white stuff around his mouth, a few days ago I got 2 Mollys (1 died) and 7 ghost shrimp and later that day I saw my betta at the top of the tank with white stuff around his mouth. There was some algae around the tank at the time. What can I do to help?

The first two pictures are of my betta and the last one is my tank.

 

[NickAu]

When posting a request for help can you please include the following info

Tank size:
pH:
ammonia:
nitrite:
nitrate:
kH:
gH:
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Fish Symptoms (include full description including lesion, color, location, fish behavior):

Volume and Frequency of water changes:

Chemical Additives or Media in your tank:

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