Fish began acting strange after introduction of new plants/fish

[ragabashryan]

I just started building my aquarium and everything was going fine until just yesterday. I have a medium sized tank that I put one Betta, a few catfish and some Tetras in. Like I said everything was fine until I introduced a Bamboo stalk and African dwarf frog into the tank. I did this just before leaving for work and came home to my Betta on the floor (he jumped out the tank) and white mold on my log and fish swimming sporadically. My Betta is currently healing in a separate tank from the trauma but may not make it. Please help me, these fish have been my everything for the past few weeks and I really wanna take good care of them.

 

[Toad]

Is it possible there was some sort of chemical on the bamboo stalk? I'd say do a major water change just in case

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[ragabashryan]

I think I found out the problem. Rookie mistake. I changed substrate when I put all that in. I lost a few more Tetras but the catfish and dwarf frog and living just fine.