For on tank MHs, i advice u can check out the Marine LFS. they carry lots of MHs stuff. Or another suggest u can get wall mounted MHs. Which i personnally think its better as u can adjust to the height u want the Mhs to be from yer tank.
C328 carries tankover type (if i'm not remembered correctly). those Mhs in a nice casing which u can place easliy over yer tank.
Cheers.
