Hiya Austin, my favorite town from the old days.
This may come in handy next time or even now:
I did a search on Maracyn-2 last night because I have some coming in.
Manufacturer said use the full amount, so I guess after opened it doesn't have a shelf life.
Best use I came up with was this:
1 pkg/10 gallon
Put 10 tbsp treated water into a container.
Add 1 medication package to it and dissolve it real good.
Then add 1 tbsp of this mixture for each gallon of water being treated.
Day 1 says use a double dose use 2 tbsp for each gallon of water being treated.
Throw away the unused medication mixed up.
It still saves on the number of packages you would use the first day.
Do 100% water changes daily no matter what the box says with the new mixes at only 1 tbsp of this mixture for each gallon of water being treated for the number of days needed.
Note Aq. Salt will irritate it and make it worse, you have to get the swelling down before you use it.
I have been using the Epsom salt method and got this just in case the ES didn't work. Finally at day 7 of that his left eye that was worse than his right eye is about the same size as the right eye is and he is moving it around thus looking with it. Before that it stayed kind of fixed. Epsom salt talks excess fluid out of the body thus the reason it brings the swelling down, but it has to be changed out 100% daily also or it becomes a problem.
Popeye has many causes so here is my shorthand notes on it:
It is a symptom, not a disease in itself and has many possible causes
Can be difficult to cure if source unknown.
Origin can range from bacterial, viral, parasitic or
dirty water=meaning high nitrate/ites, ammonia, etc.
Can be symptom dropsy & also associated with Ich or injury
1 eye usually trama based such as run into plant or something bump him
(if panic at clean time could have smacked eye into something)
Both eyes tends to be more infection based via bacteria in water
One or both eyes appear be protruding abnormally, "popping" or stick out=bacterial infection.
Eye rupture clean water EVERY DAY would be best mainly because of infection--I would do a search and post asap if that happened to decide if Epsom should be changed over to Aq. Salt and exactly how to do that accilmating the fish to the change safely.