Importance of filtration to stocking

[Dalfrey86]

Recently I had to move a mature African Cichlid to my 29g QT for healing from some fighting. My QT was a 29g kit from the big box store that came with everything but the stand.

This has been fine in the past but either I am in the midst of a failing filter or this guy makes a wicked mess in 4 days. Regardless i cannot see the back of the tank in that period and am compensating with more water changes.

My point here is that just because a filter is rated for a specific volume of gallons that does not mean it is rated for the volume of stocking. A 55g with 2 juvie cichlids is not the same bio load as a 55g with 2 mature cichlids. Common sense sure, but this is a lesson I'm seeing first hand.

My philosophy has always been to run 2 different filters, a marineland penguin and the stock topfin on my 55g tanks. Thinking more filtration is better than not enough.

Food for thought, stay fishy.

 

[duanes]

I believe when Aquarium companies rate your average filters for certain tank size, those ratings are based on a community tank of guppies, neons, or at best an angel fish, and a betta.
And are a bit delusional if applied to tanks with anything larger like cichlids. or slightly larger than few inch semi "monster"fish.
When these ratings are taken seriously, they are the reason we here at MFK see the many posts in the disease or filtration sections asking why this or that disease has appeared out of nowhere, or why the water is not clear in supposedly perfectly rated filtered tanks. These are tanks are to me obviously under filtered worse, given less than frequent enough, and adequate water changes.
The idea that filtration will actually replace the need for large, and frequent water changes in tanks with substantial sized fish, that are also almost always over stocked seems also quite short sighted, because people believe these filter ratings are sufficient.

 

[neutrino]

My point here is that just because a filter is rated for a specific volume of gallons that does not mean it is rated for the volume of stocking. A 55g with 2 juvie cichlids is not the same bio load as a 55g with 2 mature cichlids. Common sense sure, but this is a lesson I'm seeing first hand.

Absolutely. And performance of the same filter can be minimal or optimized, depending on how it's set up and maintained. Some filters are inherently capable of handling more than others of a similar rating. Using only the pre-made cartridges provided for most hang on power filters is a minimal use of the filter. Something like the large Marineland power filter (400) can actually handle a decent size tank and stock if you ditch the cartridges and fill it media that's rinsed instead of replaced constantly.

It's hard to find a video on this that isn't much longer and more verbose than it needs to be. This one isn't perfect, but it covers some of the basics and someone can customize from there. This one's longer and using his media would be pricey, but it also explains media and shows how far you can go in terms of media. I've set up hang on filters multiple ways, from as simple as nearly all poly floss, which I rinsed rather than replaced constantly, to something resembling the 2nd video.

It all varies according to tank, how you set up the filter, etc. I've had some tanks that were under-filtered by most standards, very clear water, 0 ammonia and nitrites and low nitrates, but lightly stocked. But I generally exceed a filter's supposed capacity for a tank, often by double.

 

[neutrino]

...Just to add, over the years I've found some filter models or types really can do something close to their "up to" recommendations with light to moderate bio-loads while others' recommendations are fantasy in any but a very lightly stocked tank. Example of very efficient bio-filters ime are fluidized bed filters, which I ran for some years.

 

[rich the fishkeeper]

Friendly reminder: always over filter ur tank if u wanna keep messy fish

 

[duanes]

...Just to add, over the years I've found some filter models or types really can do something close to their "up to" recommendations with light to moderate bio-loads while others' recommendations are fantasy in any but a very lightly stocked tank. Example of very efficient bio-filters ime are fluidized bed filters, which I ran for some years.

Agree with this, especially with fluidized bed filtration, although FBF does not filter out particulate or any visual component of water quality, it helps with the more deleterious invisible pollutants.
At the moment my tank hasn't been filtered or had water movement for almost 3 weeks (a power surge took out my pump, and Covid has prevented getting another so far)
and so far only 1 fish out of 15 has died, probably because it was obviously getting too large for the tank. (more than 12" L and almost 5" W, in a 180 gal).
All the rest, 12 five inch cichlids, two 4" tetras and I Pleco, all still kicking.
I believe the heavy planting and daily water changes has done more to save them, than any filtration could.

 

[jjohnwm]

The obvious problem is that the ratings assigned by manufacturers are not standardized; they are arbitrary figures that have little or no value (other than perhaps comparing different models offered by the same manufacturer). They are then taken as gospel by many aquarists, who use them in combination with other rules-of-thumb that are also considered inviolate; you know, things like inches-per-gallon of fish, or frequency of turnover of tank volume per hour, or those ridiculous "formulae" that claim to tell you just how many percentage points of overstocking you will have if you add one more guppy or catfish.

Back in the dim distant past, a popular "formula" stated that an unfiltered, unaerated, completely still-water aquarium could support one inch of fish per gallon. By adding aeration, you could double that to 2 inches per gallon; and, if you splurged and utilized that air to power a filter of some sort, you could make the jump to 3 whole inches per gallon. If I recall correctly, these "rules" were based on the idea that the aquarium was housing tropical fish; we were warned that if keeping coldwater fish (i.e. goldfish) that all those inch values needed to be cut in half, since they were apparently oxygen hogs.

All the factors contributing to the laughable impossibility of such nonsense "rules"...I think I was 12 when I realized that the rules would "allow" me to keep a 15-inch Oscar in a filtered 5 gallon tank...didn't stop folks from trying to apply them, and then wailing and wringing their hands when problems surfaced. But the interesting thing was this: it was a known and indisputable fact that fish could live without aeration and/or filtration, if two things were kept in mind. First, that the stocking density would need to be much lower. And Second, that water quality needed to be maintained by the simple expedient of frequent water changes.

And guess what? That's still true. Filters are not needed to keep fish. Using filters is simply a way of maintaining the desired level of water quality while changing less water, less frequently. Any filter will "work" in any size tank, but the smaller the capacity of the filter, the less of an impact it will have and the greater the need for water changing. Simple, huh?

So, go ahead and put that corner box filter into your 300-gallon tank. It won't hurt, but it won't help much either. The problem arises when someone does the research, crunches the numbers, reads the ad copy, drinks the Kool-Aid and drops the coin on the latest low-drag high-speed Wunderfilter, which works wonderfully for a good long while...but then fish begin to mysteriously "pass away" (family members "pass away"...fish die...). Brows furrow...google searches run...forum questions are asked, usually with plaintive PLEASE HELP!!! banners...and eventually someone mentions Old Tank Syndrome. This hoary old bogeyman scares the crap out of everybody, but...it doesn't exist. The problem should be called Old Water Syndrome...caused by using the same old water and expecting a miracle-tech filter to substitute for water changing.

I'd love to be proved wrong...but even if I am, water changes will always trump filters in my aquarium.

 

[Dalfrey86]

The obvious problem is that the ratings assigned by manufacturers are not standardized; they are arbitrary figures that have little or no value (other than perhaps comparing different models offered by the same manufacturer). They are then taken as gospel by many aquarists, who use them in combination with other rules-of-thumb that are also considered inviolate; you know, things like inches-per-gallon of fish, or frequency of turnover of tank volume per hour, or those ridiculous "formulae" that claim to tell you just how many percentage points of overstocking you will have if you add one more guppy or catfish.

Back in the dim distant past, a popular "formula" stated that an unfiltered, unaerated, completely still-water aquarium could support one inch of fish per gallon. By adding aeration, you could double that to 2 inches per gallon; and, if you splurged and utilized that air to power a filter of some sort, you could make the jump to 3 whole inches per gallon. If I recall correctly, these "rules" were based on the idea that the aquarium was housing tropical fish; we were warned that if keeping coldwater fish (i.e. goldfish) that all those inch values needed to be cut in half, since they were apparently oxygen hogs.

All the factors contributing to the laughable impossibility of such nonsense "rules"...I think I was 12 when I realized that the rules would "allow" me to keep a 15-inch Oscar in a filtered 5 gallon tank...didn't stop folks from trying to apply them, and then wailing and wringing their hands when problems surfaced. But the interesting thing was this: it was a known and indisputable fact that fish could live without aeration and/or filtration, if two things were kept in mind. First, that the stocking density would need to be much lower. And Second, that water quality needed to be maintained by the simple expedient of frequent water changes.

And guess what? That's still true. Filters are not needed to keep fish. Using filters is simply a way of maintaining the desired level of water quality while changing less water, less frequently. Any filter will "work" in any size tank, but the smaller the capacity of the filter, the less of an impact it will have and the greater the need for water changing. Simple, huh?

So, go ahead and put that corner box filter into your 300-gallon tank. It won't hurt, but it won't help much either. The problem arises when someone does the research, crunches the numbers, reads the ad copy, drinks the Kool-Aid and drops the coin on the latest low-drag high-speed Wunderfilter, which works wonderfully for a good long while...but then fish begin to mysteriously "pass away" (family members "pass away"...fish die...). Brows furrow...google searches run...forum questions are asked, usually with plaintive PLEASE HELP!!! banners...and eventually someone mentions Old Tank Syndrome. This hoary old bogeyman scares the crap out of everybody, but...it doesn't exist. The problem should be called Old Water Syndrome...caused by using the same old water and expecting a miracle-tech filter to substitute for water changing.

I'd love to be proved wrong...but even if I am, water changes will always trump filters in my aquarium.

Yup, sure the chemistry behind water dynamics is important to understand and keep in mind but ultimately water changes trump any grade of filtration.

 

[esoxlucius]

The obvious problem is that the ratings assigned by manufacturers are not standardized; they are arbitrary figures that have little or no value (other than perhaps comparing different models offered by the same manufacturer). They are then taken as gospel by many aquarists, who use them in combination with other rules-of-thumb that are also considered inviolate; you know, things like inches-per-gallon of fish, or frequency of turnover of tank volume per hour, or those ridiculous "formulae" that claim to tell you just how many percentage points of overstocking you will have if you add one more guppy or catfish.

Back in the dim distant past, a popular "formula" stated that an unfiltered, unaerated, completely still-water aquarium could support one inch of fish per gallon. By adding aeration, you could double that to 2 inches per gallon; and, if you splurged and utilized that air to power a filter of some sort, you could make the jump to 3 whole inches per gallon. If I recall correctly, these "rules" were based on the idea that the aquarium was housing tropical fish; we were warned that if keeping coldwater fish (i.e. goldfish) that all those inch values needed to be cut in half, since they were apparently oxygen hogs.

All the factors contributing to the laughable impossibility of such nonsense "rules"...I think I was 12 when I realized that the rules would "allow" me to keep a 15-inch Oscar in a filtered 5 gallon tank...didn't stop folks from trying to apply them, and then wailing and wringing their hands when problems surfaced. But the interesting thing was this: it was a known and indisputable fact that fish could live without aeration and/or filtration, if two things were kept in mind. First, that the stocking density would need to be much lower. And Second, that water quality needed to be maintained by the simple expedient of frequent water changes.

And guess what? That's still true. Filters are not needed to keep fish. Using filters is simply a way of maintaining the desired level of water quality while changing less water, less frequently. Any filter will "work" in any size tank, but the smaller the capacity of the filter, the less of an impact it will have and the greater the need for water changing. Simple, huh?

So, go ahead and put that corner box filter into your 300-gallon tank. It won't hurt, but it won't help much either. The problem arises when someone does the research, crunches the numbers, reads the ad copy, drinks the Kool-Aid and drops the coin on the latest low-drag high-speed Wunderfilter, which works wonderfully for a good long while...but then fish begin to mysteriously "pass away" (family members "pass away"...fish die...). Brows furrow...google searches run...forum questions are asked, usually with plaintive PLEASE HELP!!! banners...and eventually someone mentions Old Tank Syndrome. This hoary old bogeyman scares the crap out of everybody, but...it doesn't exist. The problem should be called Old Water Syndrome...caused by using the same old water and expecting a miracle-tech filter to substitute for water changing.

I'd love to be proved wrong...but even if I am, water changes will always trump filters in my aquarium.

I agree wholeheartedly. Water changes trump everything, water changes are why the hobby can exist. Fancy pants filtration, nitrate reactors, super heavily planted tanks, pothos jungles in your front room, etc etc etc. All make a miniscule difference to the eco system compared to a good old water change.

Best of it is, good old clean fresh water is free, and turn that tap and you can have as much as you want.

 

[neutrino]

There are so many ways to do it, it's funny to me when someone insists there's only one way, whether water changes or whatever else. The hobby certainly did exist before water changes. Some of the earliest glass box aquariums were essentially self-contained miniature ponds, with plants and algae balanced with a fish or two and water replacement, not water changes The concept was to mimic nature and be as self-contained as possible. In the early 1850s a chemist named Warrington made some of the earliest versions of a glass freshwater tank with this concept, ran them successfully for a few years, published and lectured, before moving on to soil chemistry. Some people still do something similar, size the tank right, plants, moss, get water volume to surface area right, a few smaller fish, water replacement or practically negligible water changes, not much else. I've seen tanks left for years without water changes or even feeding-- they evolved their own balance and ecosystem, tiny overgrown ponds, essentially. Not pretty but they worked.

Most of what we do now is for the sake of keeping more, larger, or messier fish per volume of water than the early days. Even if you go back in the hobby, (I had a 100 gal tank as a kid in the 60s), what you remember isn't always all there was at the time. Some say there were only bubble filters or under-gravel back then, but at least one company already made hang-on power filters by the mid 60s. Same as now, I'm not arguing against water changes, I do big water changes, but what you're familiar with isn't all there is.