Can anyone give me an idea how to complain to Petco by email!? I'm furious!

Just went to Petco today and their betas are in horrible, deplorable, pitiful, sad condition. Really ALL of them have one problem or another. You name it, fin rot, fin melt, swim bladder, filthy water. Its disgusting! The thing is they've had the same fish for at least a couple months. It's like once they started getting sick and looking like crap they just gave up! I can't even describe how furious I am and heartbroken for those fish! Oh and can you believe the audacity they have to continue selling them AT FULL PRICE. They should be giving them away at this point.

The thing is, I took pictures and I really need them to see what's going on. I tried looking up where to email complaints but kinda just went in circles on their website. I called and the lady said to go to customerrelations@petco.com. But for some reason that didn't work either. Sorry for the wall of text I'm just pissed and sick of this!