You can pour the bleach in, with the pump off. But, don't just pour it all in one spot, unless you dilute it in a 5 gallon bucket first. (As always, wear old clothes: my personal experience is that if you wear a new cotton shirt, a tiny droplet of bleach will ALWAYS splatter from somewhere and put a hole in it. I have many hole-y shirts.)

Taylor makes a OTO/phenol kit (K1000), but I recommend that you purchase a cheap local one for immediate use.