To "pick up Oscar poo," I don't know anything better than the classic "gravel vac," which is just a siphon hose with a wider tube at one end of it. You stick the wide end near the fish poo or whatever other debris is there, and it sucks it up and out the hose. You can buy one of these pretty inexpensively. You can also make one by fitting a hose on the neck of a plastic bottle (like an empty soda bottle) and cutting the bottom off the bottle.
There's also a gravel vac attachment as part of a Python water-changing system, and also all the Python imitators that are now on the market. It works just the same as the siphon rig.