New betta with cories

I got a new betta today. I put him in my 20 gallon planted tank that already had 6 cories (3 albino 3 emerald). At first the betta honed in on them (no posturing) and pecked twice. Since then he is somewhat ignoring them even when they swim up to him or past him. My dilemma is if I should remove my betta because of those first two pecks? Or should I continue to observe?

 

I cant tell you what to do, you are the one watching them.
BUT In my opinion, I think it should be ok now, he investigated, he said, "hello" he may haveve have let them know who the Alpha is. You have lots of room. But Keep watching them often!, especially at feeding time!

 

Thank you. Still going ok. It's like he lost interest and even gets out of their way lol. I will spend many hours watching for sure and I have a back up tank just in case.

 

UPDATE: Well I've watched my cute little Tabasco seemingly get along with his cory buddies. However, I'm on my third cory death and the carcasses appear to have internal trauma Soooo I'm concluding that he's a sneaky one peck killer and I moved him to a 5 gallon. Bummer. Really wanted him in my 20 planted.

 

Doubting the betta caused the death

 

Pretty sure he did because I could see internal bleeding where he pecked but he's happy in his 5 gallon alone now lol. The cories are very small.

 

It is really very unlikely. "Internal bleeding" sounds like red blotch disease a condition with a bacterial source.

 

I have kept a very similar betta with 5 false jullii corys quite successful now they pretty much just ignore each other ,only problem is the betta sometimes steals the corys pellets

 

Definitely an internal bleed, rapid. I believe red blotch is external. Necropsy showed blood around internal organs. No signs of parasites or disease. I suppose they could've hurt themselves on driftwood. However, given the same internal injury exactly where Tabasco pecked at them... and how aggressive he seems to have turned out... pretty sure that's the culprit.

It turns out my little Tabasco is very aggressive. No issues since I moved him out.

 

I had a sungold half moon betta kill a baby catfish in under 10 minutes. It had been 'sharing ' the tank for about 20 hours. it can happen. The catfish was black in color and I never opened him up for wounds. I thought it was okay because it was only for a short time and my tetra 10 gallon was pretty full. lesson learned.

I knew tank was okay because betta was okay, ie not dead, lol.

if you see the betta swimming side by side with a fish, he's sizing him up as prey - learned it the hard way. The betta is literally thinking ' I can take him!'

cories usually survive because they don't have exact swim patterns and zoom around tank, plus safety in numbers like zebras. Hard to target and size up just 1 for 'combat'


fin size matters imo. a planket moves fast, diminishing survival

my late crown tail could also move pretty fast in short bursts.


but, I used to lose 1/2 my cories until my tank had aged ( approx 2 years ago) ... cycle complete. took 6 months ( srs) to get tank stable. I lost 3 of 6 emerald cories in less than a week.

 

Very interesting! Yeah my cories are tiny babies. My gut told me not to add a new betta but I really wanted him in a larger tank. Oh well. He's happy in his 5 gallon.