I wanted to give you a shot of the new biofilter. Originally I’d planned for the biofilter to be layers of gravel and filter medium over which would float a raft of nitrate sucking plants . . . but it’s funny how things work. I discovered the roots of the plants are an awesome biofilter all on their own. The amount of debris that is released when the plants are disturbed is amazing.
The pump injects the water across the front side of the filter tank. You can see the connection to the left of the drain plug. I used a threaded rubber bulkhead fitting (tee eliminator) into which I screwed the pump hose fitting. I got the rubber bulkhead fitting here.
The flow of water travels over a small bed of crushed oyster shell (ph moderation) and swirls around the bricks that hold up the corkscrew reed and iris pot before reaching the roots of the various water plants.
To keep the roots out of the overflow I’ve got a temporary gizmo rigged. I bent a piece of pvc and connected it between the back side of the outflow bulkhead (regular plastic type) and a piece of 4″ pvc set vertically in the tank. You can see it in the upper picture. The vertical pvc has holes around the bottom to let water in. The water enters the holes and rises to flow through the bent pvc and out of the biofilter into the fish tank. This arrangement isn’t ideal, but it will work for this season. The pressure from the rigid pvc causes the bulkhead fitting to leak slightly. Next season I’ll run a piece of 90º plastic conduit from the bulkhead fitting to a hole drilled in a halved section of drain pipe which will sit on the bottom of the tank. This will be a much more attractive (and functional) arrangement than what I have now.
I don’t know if this method of filtering will hold up to a full summer of use but before I delve into rocks and filter medium, I’m gonna give it a try. And the plus side of this is, the roots are not where the fish can eat them. How great is that?!