Mine does that sometimes in my spec V
He will not stay long and has never had any damage. I considered getting a sponge and cutting it to fit if it got worse but thankfully it has not. That could be an option for you if you need it. I also place a sponge filter on the outflow to reduce the current in the tank.
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Unless the current is a Betta all over the tank and they don't have any place to rest or eat it is best to keep current as high as possible. This enables them to exercise and gain muscle mass and strength.