I dont have a Mag3 or Mag5 but I will be posting this Tunze Pump for sale.
It was just too big for my set up (20 Gallons)
Model 1073.040:
Pumping power: 300 to 3,000 l/h (80 to 790 US gal./h).
Energy consumption: 16 to 42 W (18 to 47 W)
Pumping head: 3 m (118 in.)., ?" NPT hose supports
Voltage / frequency: (115 V / 60 Hz).
Cable length: 2 m (78.7 in.).
Dimensions without outlet and suction cups: 118 x 94 x 75 mm (4.6 x 3.7 x 2.9 in.).