snipperrr
Hi! Today I noticed a small hole or divot on my angels head. Recently, he stopped eating and moving around a lot, but within the last few days he started aggressively eating and acting normal. I don’t know why it would start if it seems he is getting healthier but anyway I need help. Here’s a picture and more will be attached. It’s up and to the right of his eye

I don’t know what to do and have never seen this so please help. I have a small hospital tank ready if I need it. I also have a bottle of Pimafix at home already. Please help me and tell me what to do.
Here is all the info for the emergency template if it’s needed :
Tank
What is the water volume of the tank? 29g
How long has the tank been running? 6 months
Does it have a filter? yes
Does it have a heater? yes
What is the water temperature? 80
What is the entire stocking of this tank? 3 angels, 5 guppies, 2 harlequin rasbora, 1 otto, 1 mystery snail
Maintenance
How often do you change the water? every week
How much of the water do you change? 25%
What do you use to treat your water? tetra aquasafe
Do you vacuum the substrate or just the water? both
*Parameters - Very Important
Did you cycle your tank before adding fish? yes
What do you use to test the water? test strips
What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Ammonia: doesnt say on the strips i use, but should be low
Nitrate: 5
Nitrite: 0
Total Hardness: 300 (I live in a desert so its really hard)
Chlorine: 0
Total Alkalinity: 80
pH: 8 ish
Feeding
How often do you feed your fish? 1-2 times a day
How much do you feed your fish? they eat it all in like 1.5 min
What brand of food do you feed your fish? tetra flakes and blood worms
Do you feed frozen or freeze-dried foods? yes
Illness & Symptoms
How long have you had this fish? 6 months
How long ago did you first notice these symptoms? today
In a few words, can you explain the symptoms? already did above
Have you started any treatment for the illness? no
Was your fish physically ill or injured upon purchase? no
How has its behavior and appearance changed, if at all? explained above

I don’t know what to do and have never seen this so please help. I have a small hospital tank ready if I need it. I also have a bottle of Pimafix at home already. Please help me and tell me what to do.
Here is all the info for the emergency template if it’s needed :
Tank
What is the water volume of the tank? 29g
How long has the tank been running? 6 months
Does it have a filter? yes
Does it have a heater? yes
What is the water temperature? 80
What is the entire stocking of this tank? 3 angels, 5 guppies, 2 harlequin rasbora, 1 otto, 1 mystery snail
Maintenance
How often do you change the water? every week
How much of the water do you change? 25%
What do you use to treat your water? tetra aquasafe
Do you vacuum the substrate or just the water? both
*Parameters - Very Important
Did you cycle your tank before adding fish? yes
What do you use to test the water? test strips
What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Ammonia: doesnt say on the strips i use, but should be low
Nitrate: 5
Nitrite: 0
Total Hardness: 300 (I live in a desert so its really hard)
Chlorine: 0
Total Alkalinity: 80
pH: 8 ish
Feeding
How often do you feed your fish? 1-2 times a day
How much do you feed your fish? they eat it all in like 1.5 min
What brand of food do you feed your fish? tetra flakes and blood worms
Do you feed frozen or freeze-dried foods? yes
Illness & Symptoms
How long have you had this fish? 6 months
How long ago did you first notice these symptoms? today
In a few words, can you explain the symptoms? already did above
Have you started any treatment for the illness? no
Was your fish physically ill or injured upon purchase? no
How has its behavior and appearance changed, if at all? explained above