Hi teo,
Suggest you go for the for the Tunze.
For your tank size the SEIO will not be strong enough
to create sufficient water movement.
I feel that SEIO pumps are over-rated... the flow rate doesn't
feel as strong as the rated specs.
Spare parts for Tunze are more readily available, but not for SEIO pumps...
I regretted buying the SEIO M1100
The SEIO pump(brand new) I bought stop working after 4 days
When i tried to remove the propeller to check i accidentally broke the
ceramic shaft. Then i found out that no spare parts are available to
replace the broken shaft