my DIY CO2 reactor/diffuser for HOB filter
I got tank with HOB filter, so inline CO2 reactor outside of tank is not possible.
I've tried different types of diffusers/reactors, they either take too much space in tank or create soda water.
Finally I tried obvious solution - reactor that uses already available water flow from outlet of HOB filter.
Design should be clear from pictures - it is a L shaped box with small hole
in a long side so that water goes but CO2 injected from below doesn't bubble through it.
Size of hole should be individually adjusted for particular filter.
If hole is too small water will overflow from top of reactor.
If hole is too big CO2 will bubble trough it.
Reactor is made from acrylic, glued with superglue and silicone.