I modified the DIY GFO reactor. The pump I was using had a little insert to step down to roughly the same diameter as R/O tubing. So I used that at first. A couple days ago, I removed that insert and used some 1/2" tubing. That increased the flow and the GFO is tumbling now and there is a ripple on top of the water so the flow should be decent. I'm going to use it for a while and see if it hardens or stays in particles. I figure if it stays in particles, should be good. I did notice a little bit of GFO leaks on startup. I put it up in the tank so I could observe it under water and saw that. But I'll leave it in the sump. I had a few minor spills too. I think I can clean these up if I get some small tubing to use as a siphon. Or maybe one of the crazy strong magnets would work (not long term, just glue it to a chop stick and pass it over the spills for cleanup).