My poor fish

I need to do something about my pond. Oh, now, it's not a big ol' pond. It's not even a natural pond. It's a little hole that Roni and I dug and placed a pre-formed plastic thang (that is not a typo) in it shortly after buying this house. I think it's about 8'x5' (ish). Anyway. When we first put it in, we bought 4 Comets and we got a bullfrog tadpole. That tadpole was huge. We watched it grow and grow and start to form legs. I used to worry that I was going to hear a knock on the back door one day and open it to find one big mother fucking frog standing there like something out of a B horror movie. The tadpole did manage to turn into a frog without paying a visit to my doorstep, but then he disappeared! Where the hell did he go? We live in the freakin' city. It's not like there was a whole lot of choices for him...the 4 Comets were all found floating belly up one day. Fine the day before, belly up the next. We think, but cannot prove, that the neighbors gardeners sprayed some damn poison in her yard that drifted into the pond. I loved those Comets. Yeah, I'm a freak, but I've told you that I'm an animal lover already. They were tame and I used to hand feed them. Yes. I hand fed my fish. I actually cried when I found them floating in the pond. What adult cries over goldfish?! God, I'm annoying even to myself sometimes. After they died, I drained the pond and bought some Fantails. One got picked off by some renegade wildlife (I found the carnage) during the winter months. At least one of the other ones had babies. I was so excited when I saw the itty bitty things swimming around in the pond that it actually brought tears to my eyes (I think I'm peri-menopausal with all the tearing up that I've been doing the last couple of years...it's so damn annoying to be so emotional! I don't know how you weepy types have done it all your lives). Anyway. The years went by with an average of one fish per winter being killed by something (there is a suspicious cat that I've seen skulking around the pond in the winter). This year I was (and still am) down to one of the original Fantails. He(?) is the only one left. His name is Marco and he was the very first one that excited the plastic bag when I put it into the pond. He's watched his buddies get picked off one by one and I hope he's been taking notes to protect himself. I meant to get him some friends this summer, but with the adoption, I never got around to it. Now I feel guilty. I've been ignoring him terribly. Do fish have emotions?