Help! fin rot! How to treat?

I am afraid that my Betta may have fin rot. I've been doing water changes every other day since I've noticed. I've even did a full water change last week. I can't tell if it's getting worse, but not his scales on his gills look like they may be peeling up. Since he gets excited when I stand in front of the tank the pics are alittle blurry. But the little white spite on the on side of his face looks to be peeling alittle and the spots on the other sides of his face don't look bad but it's hard to tell what it could be. He does not have ich. The white spot behind his gil is just his color pattern on his fin he was fluttering quickly.
I'm also afraid he may have hole in head disease.
If anyone can give me some treatment or tell me what this may be, I'll take any suggestions.
He has an appetite and he's active. He's not seeming sick.
ph: 7.5
Amonia: 0
Nitrite: .5
Nitrate: 10

I was looking at Bettafix but I'm seeing mixed opinions on that. I can't use aquarium salt in the main tank because of my snails, though I can move them into a separate if need be.
Here's one photo
Second
And third photo. Sorry about the fuzziness. It's hard to take a good picture of him

 

best thing for fin rot is clean water. it is concerning that you have some nitrite levels, is/was the tank cycles? an established tank should always have 0 nitrite, anything above 0 can be detrimental to a fish's health. I would do a water change to get that nitrite to 0 and make sure it is cycled. I am not seeing anything that looks like fin rot, looks like you have a crown tail betta which is supposed to have a ragged looking tail if that is what you're referencing? and what makes you think he may have hole in head? I'm not really seeing anything, are you able to get a more close up image of his head? Never use Bettafix as there is a chance it could damage the fish's labyrinth organ inhibiting it's ability to breathe, it's not worth the risk, it has been accountable for a number of betta deaths.

 

It is cycled. The nitrites jumped a tad due to a recent partial water and substrate change, though they are dropping now luckily. It's definitely something wrong due to his scales popping up off of his gills. His fins are fine, just used a generalized term because it seems like he has something going on with his gills that may be the same bacteria as fun rot after some research.. I just don't think it looks good honestly. Hes acting normal and there's no redness.
I've been doing 25% changes every 2-3 days as well.

 

It is cycled. The nitrites jumped a tad due to a recent partial water and substrate change, though they are dropping now luckily. It's definitely something wrong due to his scales popping up off of his gills. His fins are fine, just used a generalized term because it seems like he has something going on with his gills that may be the same bacteria as fun rot after some research.. I just don't think it looks good honestly. Hes acting normal and there's no redness.
I've been doing 25% changes every 2-3 days as well.

nitrites should not jump up if water changes are completed correctly, if you are getting nitrites after water changes then you are either using a water source that is not suitable or you are removing too much substrate therefore removing too much beneficial bacteria. depending on how long there has been nitrites in the water the peeling on the gills could be damage from nitrite levels, its hard to see in the pictures, is it the actual scales lifting or is there some sort of fungal infection on top of the gills? could be columnaris? have a look and compare it to google images of columnaris

 

Definitely not columnaris. I mean, my guess it could have been stress from the substrate change. Before the change all the levels were 0. Everything else stayed the same after the change aside from the nitrite. Though it was only Friday since it spiked. Assuming it was the tap in using, I am watching that color slowly change to zero every day I've been testing it.
I already established a cycle though so the nitrites are going to clear within the week.

 

Definitely not columnaris. I mean, my guess it could have been stress from the substrate change. Before the change all the levels were 0. Everything else stayed the same after the change aside from the nitrite. Though it was only Friday since it spiked. Assuming it was the tap in using, I am watching that color slowly change to zero every day I've been testing it.
I already established a cycle though so the nitrites are going to clear within the week.

if the tank is properly cycled, there should be no nitrites at all though, even if a small amount of bacteria was removed. normally in a cycled tank the levels are not all 0, there should be a nitrate reading. how long has the tank been running and how long have you had the fish? the issues with his gills is probably down to stress from that nitrite. have you tested the tap water you are using? if there are nitrites in that you are probably better getting an RO/DI system or using bottled water of some sort