TFA101

OMG!!! I just found a HUGE spider drowning in my aquarium and it looked as if were releasing some chemicals from its body. I fished it out, killed it, and quickly changed the water in my tank. Had I not cleaned it, would it have been a problem?

Sam Livingston

Most likely not, the releasing of chemicals has me dumfounded so someone else will have to fill you in on that. Chances are a carnivorous fish would have taken a few bites of him, he would eventually drown and be awaiting your return to scoop him out. People forget sometimes that in the wild there are 1000's of insects in the water swimming (or drowning) along side the fish. Unless the spider is poisonous or diseased then no harm would be done.

COBettaCouple

I'm not sure that it would have been a problem, although when I had a spider drop into the Angels tank, I did a 25% water change a couple days in a row to be on the safe side and kept an eye on the fish.