hi everyone im new to this site and somewhat new to fishkeeping.so to the point one of my bala sharks is acting very weird.i put him or her in the tank yesterday and tonight i noticed it was acting as if it had a swim bladder issue,but upon firther inspection i have noticed alot of red behind its anal fin.all of my other fish are doing absolutly fine and i do not have any water testing kits here but i will be going to the pet store tomorrow and get them to test it for me.so if anyone has any info to give me with the info i gave you much appreciated.