Betta Fish: Do you think this is ich?

– 5 gallon tank
– Sponge filters x2, no heater
– Temperature fluctuates between around 73-83°F depending on the weather
– Ammonia 0, nitrites 0, nitrates 0
– Had tank since late August (preexisting media from other tank), betta since late September
– 10-20% water changes weekly, using a small airline tube
– Tankmates? Grass shrimp (numerous), ramshorn snails, Malaysian trumpet snails, scuds, limpets, copepods, detritus worms
– Feeding seven or so TetraBetta Select floating mini pellets once per day during weekdays, smaller amounts around twice to three times a day on weekends and holidays
– Lava rocks and aquascaping wood as decorations
– Numerous aquatic mosses and liverworts as plants