I bought 2 k nanos and ended up giving them away. You can blow more water around by sticking you head in the tank and screaming. Seriously, they SUCK!dawgdude;177236 wrote: I had one tunze 6025 in it and my sand bed was being completely disturbed by it and my diamond goby was MAD. I dropped down to one K1 and might go with two K nanos on a wave maker. If I put SPS in there I will probably keep the K1 in all honestly. I have a moderate amount of flow in my 30 cube and my SPS in there has incredible polyp extension, amazing color and stellar growth.