Can cory's get finrot?

[duendecillo]

I have a 10g tank with a male betta and 2 females (not fighting or anything)
But I think the male has finrot.
I was planning on putting some cory's in the tank. Should I not do that now? Because of the risk of contamination?

 

[Big_al_d]

Before adding any fish at all, I would be inclined to sort out the current problem.

What are the water params?

 

[duendecillo]

We use different units, but nitrite, nitrate, ammonia, ph, kh is okay
gh is high, hard tap water, but never had real problems with that...
temp is 78

The male betta already had a brown spot when I bought it...

There is some blue stuff in there I got from the lfs, but from what I've read on the label, it's actually more for white spot...

 

[Inchworm]

Hi duendecillo

Never put a new fish into a tank where there is any kind of disease.

Fish develop finrot from bacteria that is always present in a tank. When a normally healthy fish is exposed to conditions that weaken its immune system it becomes unable to fight these bacteria and finrot is the result.

Some of these conditions are high nitrites levels, low oxygen content in the water, sudden increase of temperature, uneaten food in the tank, infrequent water changes and overcrowding.

If you suspect that your fish has finrot, look first at your cleaning routine and try to find out if any of these things have happened. If so, make whatever changes are necessary to correct them. Lots of clean fresh water will do your fish a world of good!

MelaFix and BettaMax are two of the products that are often used to treat finrot in bettas, so give one of them a try before adding new fish.

Remember that new fish are often exposed to the conditions that leave them open to finrot while they are being transported to or at the lfs, so they are sometimes weak when you get them.