external heater

Hi folks, first time poster here. I'm relatively new to the hobby - had a simple 60L community tank for a couple of years and now in the process of upgrading to a 120L with an external filter (Fluval 107). I hate the way heaters look inside tanks, and have been looking at external in-line...

Equipment: Hydor ETH 300w external heater. Comes with instructions and box. Age and condition: about 10 years old. In excellent condition. Used for about 2 years and in storage for remainder of time. Quantity for sale: 1 Reason for Sale: no longer needed (downsizing) Delivery or Collection...

Sat down tonight watching my tank, and suddenly heard a pop type noise, checked the filter (ex1200) as i had changed the basket orientation earlier, and then the filter started to make noise as if air was in the system, then checked the inline heater and found that it was leaking, as i moved it...