joltibo
Aquarium Advice Regular
I just wanna point something out since its in your pic. That heater is NOT made to be fully submerged. It has minimum and maximum water lines on the glass part of it. I would raise it out of the water or risk all your fish dying. Sorry it was off topic. I hope everyone with a fluval heater see's this.
Edit. You can actually see the water lines in the pic. I would raise it to that first line below the plastic.
Raise your heater to between the lines!!