Red Cap Fin Rot in main tank

[vijayw]

Hi,

30 gn tank
4 Tinfoil
4 Koi
6 Tiger
1 Sucker
1 Angelfish
+ 1 Red Cap

Earlier I had 4 Red caps, 3 died over a period of 2-3 months.
I observed its tail was damaged too much. This happened with all Red Cap but one after the other, I separated it in a small bowl, without at filter/gravel/heater. I added few drop of Mr Blue medicine in the bowl.

The Red Cap stays well in bowl, infact recovers in few weeks time. But when I put them back in main tank, the fin rot appear after some time.

It is fish compatibility issue? Though I havent noticed any other fish troubling it.

Should I add Mr Blue in main tank as well?

Is heater (warm water) troubling Red Cap?

Is my Red Cap happy in living alone in a small bowl?

 

[charliebankston]

You should do some reading on fin rot. Water conditions etc. Mr Blue is a fungal medication, fin rot is bacterial. It's getting better during treatment because of better water conditions than your tank, tbh. The methyl blue meds really aren't doing anything to cure fin rot

 

[charliebankston]

Just fyi, to help solve part of your problem, is your tank is grossly overstocked. 30g is not big enough for tinfoil barbs, angel fish, "sucker" fish depending on the species

 

[charliebankston]

*oh, or Koi

 

[vijayw]

Oh, my bad. Thanks.


Water:
I change 20-30% water change every two weeks with Gravel vacuum. Water is all clear.

Overcrowded?
All the fishes are very small.
How to calculate that tank is crowded?

 

[charliebankston]

At a really small size, it might not be that overcrowded yet, but all those fish i listed require a much larger tank than a 30g unfortunately. The tinfoil barbs can reach 12" in length. That's the whole width and 1/3rd of your tanks length, lol. More fish means more harmful bacteria in the water column. Requiring more water changes. To avoid bacterial infections like fin rot, etc

 

[vijayw]

Here's an image of my tank.
Even with these (so many) fishes, my tank looks empty only

 

[charliebankston]

It's a very pretty tank, good job on aquascaping . They'll grow fast tho, it'll be full soon. Part of the fun of keeping fish is getting them little and growing them out in your tank. You can look back at pics and see how little they were. Almost like kids, haha! Instead of changing nappys you change water

 

[vijayw]

It's a very pretty tank, good job on aquascaping . They'll grow fast tho, it'll be full soon. Part of the fun of keeping fish is getting them little and growing them out in your tank. You can look back at pics and see how little they were. Almost like kids, haha! Instead of changing nappys you change water

Thanks!!

However they, for most of time they remain at bottom only. Come up only when I feed them.

These are my first fish. But I wanted more colorful and bigger ones in my tank.