Need some betta advise/reassurement

[zaphekiel]

All right, so excuse my longer post... Ok, so I have had my 5gal up and running for 2 months now, fully cycled 0/0/5-10ppm (as per this afternoon) with my resident Otocinclus who by the way is one cool dude :)

My issue is this: I have gone through 2 bettas in the last 2 months. They both caught what looked like body fungus on day 2 and died within 72 hours of purchase. I have the freshwater API kit and test regularly so I did water changes as needed so I doubt the water quality was the issue. I decided no more petstore bettas (I tried 2 different stores) and am ordering a HMPK from a breeder. He should be here next week as he will be 12 wks old and able to ship. However, I have fears that this more expensive fish will have the same fate as the last two... despite the cost I will be more upset if he dies... and I feel like I am a terrible fishkeeper...

So.. any advise on how to avoid this for my new fishy? I feel like I did everything I could... and yet.. Also, any different care for the young 12 week old fish? I heard you are supposed to do daily or every other day 50% changes due to a hormone they secrete, anything else I should know? I really want this to go perfectly so any and every knowledge ya'll can send my way please do so!

Thank you!!!

[bethyMT]

Hmmm...I wonder if there is some bacteria or something in that tank that is getting to your bettas. Others will be along shortly to help. Bacteria and fungus are pesky critters.

And, I've already given you my advice. They are hungry little dudes, feed three times a day and they'll still be begging!

I'd call them almost-teenagers, these 12 weekers. Not babies anymore, but not grown yet either.