I do like redundant filtration, but that is more in parallel than in sequence. I freely admit that some of my long-ago SW tanks had mech & bio canisters feeding their outputs to RFUG. Having a biofilter feeding a biofilter, hmmm - it finally dawned on me that the first in the sequence was either not doing the job, or why did I need/have the second in the sequence? So I dropped that habit. I also am too lazy to open a canister at least weekly for maintenance.
I really don't like or use conventional flow UG anymore, not in a long time. It serves all too well as a mechanical filter and thus requires significant maintenance. I prefer RFUG with a prefilter for mechanical first, before the gravel bed gets the water for biofiltration. That is a comparable setup to FBF, and IMHO, a valid one. Biofilters do not "need" to see any particulates. It is much easier/faster to rinse a sponge weekly than to vacuum a couple of square feet to tank fully and carefully. With RFUG you only need just more than surface vacuuming - to get the big chunks such as pleco poop. But I do use secondary mechanicals for current and to help capture particulates of all sorts in all of the RFUG tanks.
Perhaps the guy who was worried about competition between units has only old carbon as his biofilter? It would sort of fit the profile, wouldn't it? It also unfortunately fits the profile of someone who had a thought, pondered on it a while, decided it was correct, and therefore it is correct now and forever. Nobody ever told him that the proof of the pudding is in the eating. All ideas must be real-world tested and shown to be true, or not to be true. Thought is extremely valuable, but it is not a laboratory, or even a fish tank.
I really don't like or use conventional flow UG anymore, not in a long time. It serves all too well as a mechanical filter and thus requires significant maintenance. I prefer RFUG with a prefilter for mechanical first, before the gravel bed gets the water for biofiltration. That is a comparable setup to FBF, and IMHO, a valid one. Biofilters do not "need" to see any particulates. It is much easier/faster to rinse a sponge weekly than to vacuum a couple of square feet to tank fully and carefully. With RFUG you only need just more than surface vacuuming - to get the big chunks such as pleco poop. But I do use secondary mechanicals for current and to help capture particulates of all sorts in all of the RFUG tanks.
Perhaps the guy who was worried about competition between units has only old carbon as his biofilter? It would sort of fit the profile, wouldn't it? It also unfortunately fits the profile of someone who had a thought, pondered on it a while, decided it was correct, and therefore it is correct now and forever. Nobody ever told him that the proof of the pudding is in the eating. All ideas must be real-world tested and shown to be true, or not to be true. Thought is extremely valuable, but it is not a laboratory, or even a fish tank.
