Just wondering, im trying to do it right and have a decent nano reef going. my last one failed from lack of water movement. dead spots, algae, yada yada yada... so now im looking to get some good movement and don't want to skimp since it will only ever be this 20 gallon nano. but i'm looking at the VorTech pumps since its got the wave maker options to it. my question is, im looking at the VorTech MP10 which is for 2 1/2 to 50 gallon. or should i consider the VorTech MP20 which can do 20 to 70 gallon? since it has adjustable flow rates im thinking the MP10. but will i need more then one pump or will the one pump be ok?