I would go with the maxi mod or if the budget allows, a vortech. I have always been a fan of atleast two PH's in the tank. You need some redundancy. One PH is never enough for a tank, there is always the possibility it will stop working. I have had Tunze streams lock up and vortechs fall off the glass. You could get a vortech and a maxi! They dont all have to be the same PH brand.