I watched a video on youtube on a cheap DIY fish catcher using a plastic coke bottle, cutting off the top, inverting it back into the bottle, baiting it with food and pulling it out, so I will try that, sounds simple enough, but I'm sure that they will just make an idiot out of me. Both blennies high tail it back to the back of the aquarium when I show them the net, because when I am in front of the aquarium they both are right up by the glass, and as soon as I even look like I may be going for the net, they vanish into thin air, er water. Normally one blenny hides in some rock where there are 3 rocks together forming her hiding hole and the other goes up and hangs around the top of the protein skimmer draw tube. The other blenny will leave her hole and swim up to harass the other one. They don't really totally duke it out, it is just a quick nip and the other takes off, then goes right back to the tube. It's like one thinks she owns the aquarium and the other justs ticks her off.