Hi bro,
I have the same problem too so I replaced it with Enductor Fluidized Reactor- FR30. IMHO, TLF initial design is mean for running po4 and carbon media so my advice is better use bio-reactor instead.
sorry ! Was too busy with work ! Not much changes for the tank added a multibar angel and a pair of helfrinchi gobies only.
Waiting for my cr , fr and kr to arrive !