Sick sixline wrasse

[Natelb44]

My sixline has patchy looking scales and a cloudy eye that has come and gone away a couple of times. I have treated by adding seachem focus and garlic guard to his food for 5 days. He still has a good appetite and is active should I try using something else such as paraguard which I bought the other day?

My parameters are
Nitrate-0
Nitrite-0
Ammonia-0
Ph-8.1