Finally upgraded to 20g, now fish have fin rot. Can I do ParaGuard baths?

[ashleykw]

I now have a 20g with 3 male platy, 1 male guppy, and 1 male betta (separated by divider). Before we moved, I had my betta in a 3.5g and thought I noticed his fins tearing but only assumed he may have cut it on something because it was relatively unnoticeable and he was otherwise healthy. Now, I’m noticing it even more and it’s getting worse. One of my platy seems to have it too, but his hasn’t been getting any better or worse. He used to be in a 10g with the other platy and was the only one showing signs of fin rot.

1. Should their fins grow back after successfully alleviating the fin rot?
2. I have ParaGuard and the instructions say “for 1 hour dips, use 3mL per 1g.” How often should I repeat this? I was thinking of using a large bucket I use for water changes to give him the baths, and giving him and the platy separate baths.

Thanks!

 

[ashleykw]

Here is a photo of my new tank.

 

[coralbandit]

I would think in tank treatment might be less stressful ?
I have never used paraguard but here a good link from someone who did for just what you are dealing with I think ?
https://www.google.com/url?sa=t&rct...-897429.html&usg=AOvVaw0L33BvZWkEQtN6E1rbCuU8

 

[Angellove78]

Have you tested the water?

 

[ashleykw]

Have you tested the water?

Yes, since moving I did one 25% partial water change and checked parameters the next day (yesterday)
Ammonia - 0
pH - 8
Nitrite - 0
Nitrate - 5 to 10ppm

I figured the tank would cycle quickly since I used the same gravel mixed with new gravel, same filters with same cartridges, and same decor. I was careful to keep everything wet during the move as to try and not kill the beneficial bacteria (as someone once told me). It’s been frequently recommended to upgrade to a larger tank to avoid drastic water parameter fluctuations that are more commonly seen in smaller tanks. Sad to see my fish just rotting away, I feel like another platy has a tattered tail fin now :/. Thinking I might go with treating the whole tank. Wish me luck!