Community Tank Setback

[betterfish]

Hello all,

Unfortunately, I am having a few setbacks with my community tank. It is a ten gallon and houses 8 tetras, a snail, and my betta, Scarface. Before about 2 weeks ago, I only had 5 tetras. I stopped by PetCo and picked up a trio of tetra to try to coax the 5 tetras out of hiding (they seemed too timid to school and never came out of the "forest"). However, I came to the realization after getting home that I do not have a quarantine tank... So, I just acclimated them to the tank as usual, and after the necessary time, I let them in with the other fish. It worked! The 8 tetra now school happily. It seems, though, that these fish did not come without their share of issues...

Just last week, I came home and noticed one of the tetras had only one eye! He was very timid and swimming a little oddly, so I took him out and separated him for a few days in a small bowl. He didn't seem any happier there, but he was eating normally and swimming better, so I placed him back in the tank. He is doing fine now! Still, something to be concerned about.

I have taken Scarface out of the tank because he was swimming/sinking/floating strangely. He just wasn't acting himself. He is now in a small bowl by himself, doing better. I think he had a little bloat and/or constipation. I will keep my eye on him closely for the next few days. He hasn't pooped in a couple days, which has me worried...

And lastly, I am starting to see little white spots on the tetras. I am nearly positive it is ich. One of them even has a little fin rot going on. My question is this: when it comes to medications, is an all in one better? I am looking at purchasing Tetra Lifeguard All-In-One Freshwater Aquarium Treatment. It says it treats a wide variety of things. Would this be a wise treatment for the potential fungi and/or bacterial "goodies" in my tank? Also, should I put my betta back in the tank for treatment? I will fill out the stock questionnaire in the next post. Thanks!!

[betterfish]

Housing
What size is your tank? 10 gallon
What temperature is your tank? 80*
Does your tank have a filter? Yes, Tetra Whisper 10
Does your tank have an air stone or other type of aeration? No
Is your tank heated? As of 3 days ago, yes.
What tank mates does your betta fish live with? 8 tetras

Food
What type of food do you feed your betta fish? Betta pellets and tropical flakes
How often do you feed your betta fish? 2x daily

Maintenance
How often do you perform a water change? Once a week
What percentage of the water do you change when you perform a water change? 25%
What type of additives do you add to the water when you perform a water change? AquaSafe

Water Parameters:
Have you tested your water? If so, what are the following parameters?

Ammonia:
Nitrite:
Nitrate:
pH: 7
Hardness:
Alkalinity:
(all good, I have an all-in-one test kit that says all parameters are fine)

Symptoms and Treatment
How has your betta fish's appearance changed? None for my betta. Tetras have little white spots. One also has one eye. Another has shredded fins.
How has your betta fish's behavior changed? Lethargic, floating/sinking problems, resting on the thermometer (close to surface for air), not fanning his fins out like usual. With my tetras, not change in behavior.
When did you start noticing the symptoms? 3 days ago
Have you started treating your fish? If so, how? No treatment yet. Will treat asap!
Does your fish have any history of being ill? None! Scarface (betta) has been through A LOT and has survived!
How old is your fish (approximately)? Scarface is probably about a year and the tetras are probably the same.