Anyone running a Tetratec EX filter would be advised to make extra checks as I have discovered.

Some filters have a problem in the motor head with a part that allows the motor head to fill with water then leak down the side of the canister. Very annoying is the fact that my 4 month old cabinet is now swollen at the base (being absorbent chipboard) and the veneer coming off where over the last week, water has been seeping out slowly (so slow that in a large tank, water level drop was negligible, allowing for heat and evaporation)

Apparently Tetra are aware of this being a problem on some EX series models, though I am waiting for a response from their warranty claims dept - hope they hurry as I only have my backup Fluval internal filter struggling to cope.

New ones apparently have an improved internal seal in the head unit to prevent the problem - I bought mine last November but didn't install it until I finally got a new tank at easter