External pump reccomendations 400gph apprx

[banditpowdercoat]

Like the title said. I am removing the pump from my sump. Presently using a Mag 3.5, but found the outlet cracked. I over tightened the fitting. So, needless to say, only could half upgrade to my new sump design LOL. Now, I want an external, for the less heat introduced, and more space in sump. 10g sump is small enough.
I have a mag 18 here if anyone has sometinhg smaller theyd like to trade. If now, what is best bang for buck? I dont want to leak, thats for sure