One, the Hydra, would be perfect. The other, Hydra 52, is overkill.
So you can get both and run the Hydra around 40-65% or you can spend more money and get the 52 and have the percentages around 15-30%.
Hydra 52 is for deeper tanks. Yes, both can be used on any tank but it makes zero sense when the Hydra can do the exact same at slightly higher %'s.