Box Or Bed?
It's late kids, so I want to tell you a story about how things once were.
Once upon a time, all indoor tropical fish aquariums had undergravel filters. That was all there was. Or no filtration at all. Some tanks only had gravel, plus a piston-type air-bubbler. And the fish did fine. And we didn't even know to 'siphon clean' the gravel. But some fish eventually *didn't* do fine, and collections of fish died every once in a while, and we didn't really know for sure why. Water quality sagged, and quarterly or biennial "upheaval" was the modus operendi.
Then, a progressive person invented the submersible box (charcoal and floss) filter. And things were a *little* better except in truth, a little submersible box couldn't keep water as pure as the expansive, traditional undergravel filter.
Then *another* person finally invented the "big" external filter for the tropical fish tanks. It went from box, to canister, then wet-dry, trickle and reef. And the Undergravel filter was simply discarded along the way for its inefficiency.
Then someone (who was probably very young) said that undergravel filters were "bad", and "didn't work". But the person was just inexperienced. By their youth perhaps, they were unaware that undergravel filters were merely inefficient, and a nuisance to keep clean for tip-top operation. But undergravel filters weren't "bad". And they DID work very well. Why, they had worked for all of 'aquarium-history' until they were replaced in some systems by more comprehensive, easier to maintain systems.
There was *one* big difference between the undergravel filters and external box filters though:
When the undergravel filter got clogged and channelled, water quality deteriorated but the water continued to *move*, and fish managed to live quite a while longer. This is how the gravel bed water gardens are.
When the box or canister filter clogged, it either overflowed and flooded the living room, or simply quit flowing, and the fish suffocated and died. This is sometimes how the box and bead filters can be.
Advanced Aquascape™ pond, two-belly design, 6x6 upflow aggregate filter w/ 9,000gph pump feeding falls.
The one type of filtration is easy to maintain with relatively simple, frequent interval-attention. On the other hand, the undergravel would work for a long time with no attention, but then you had to tear it down.
And so it is today that people discuss, on a much larger scale in ponds, the age old question of gravel filtration versus external 'box' filtration....
Gravel filtration, which can be considered 'simple to maintain' through planned or inadvertant neglect, or could be considered troublesome if sparkling gin clear water under populous stocking densities is the goal. Gravel filtration is actually *more* difficult to maintain PROPERLY, and usually necessitates cataclysmic cleanouts once or thrice per year...
Gravel filtration has always been like that....versus external filtration which benefits from frequent attention in small amounts but which sometimes won't even flow if clogged.
Since I personally can be gone for weeks to a month at a time, and since, in my absence, I have lost valued fish to filter-failure due to simple clogging, I can easily appreciate a pond that still works even when neglectfully glutted by sh*t.
I can also appreciate the contrary; that if I had weekly small allocations of time, I could twist or pull a knob on a Vortex or bead filter running a clean-bottom pond and clean the pond in my Sunday clothes.
I see criticism of the undergravel filter. But they are not too-unlike popular gravel filled barrel and box filters. ALL filtration catches and holds fish wastes within the water column. Some are just much easier to discharge than others.
So gentle reader, what you have to ask the customer; is if they want a formal "filter" to manage, which is easy to clean but necessitates their interval-attention, manipulation and observation of flow rates, while giving them gin-clear water ---- or do they want a natural bed of gravel that will allow them to essentially 'forget' the bio-mechanical side of the pond for a lengthy period of time but which will eventually and inevitably, (to be "done right") require substantial and disruptive upheaval in a possibly-expensive scheduled-service cycle?
You'd be surprised how many people would choose the simplicity of an external filtration method which gives satisfactory results with weekly observation, and maintenance-attention.
And you will *also* find folks who, when presented with the above information, choose the comparative simplicity of seasonal cleanouts, done by someone younger and stronger than them. And with (optimistically) education, they can subscribe to the lower stocking densities necessitated by gravelbed filtration. But their ponds *will* work, and they will be happy with them, and they won't be "wrong".
Consumers and installers have to be (and can be) informed about their choices and what the relative benefits AND CONSEQUENCES are. Given a choice, and proper education, consumers will choose a method that works for them and their lifestyle.
We have the challenge to educate everyone, from installers to consumers, so they can present these choices to the Newbies and let them pick something that fits their energy and income level.
Good night then,