Yes, but what's KI reactor?
In Uni we had a gorgeous 85gal and no money. Had 2 cheep little HOBs from a yard-sale and set them to opposite ends of the tank front & back so the surface current went in a circle. We then filled plastic soda bottles (1.5l maybe) with fine gravel and punched a thousand holes in lower half, mainly the bottom. We then shoved the end of the HOB inlet (with screen) into the top of the bottle and through the gravel: Voila- massive surface area.
Plus massive planting and an air-stone.
Helpful?
A