I just added an Eflux 660gph to my new 20 gallon Tall frag tank build. Looking for any info from someone with experience with small frag systems and or these power heads. Should I put 2 of them in the system? where should I place them? How well do they function? what setting would you recommend in a frag tank and with them? This is our first attempt at a frag system it is part of my classroom Reefing project. I had the eflux in a Bio cube in Kansas but just left it on stream all the time in that tank. I have the one powerhead placement on right side kind of low in this tank? Really want the kids tank to grow coral!!!