OVERFILTRATION

[Hybridfish7]

What's a good goal to shoot for in terms of overfiltration? As my current plans stand, my lowest filtration to tank volume ratio will be 1.5:1. My highest will be 12.5:1, inbetweens being 3.25:1 and 10:1. I feel like the 1.5 is too low for my liking, even though it's a 29 with a pair of cichlasoma dimerus.

 

[skjl47]

Hello; I generally find this sort of thread to be a modern day question. I started keeping tanks in the 1950's with only air bubble operated filter systems in my tanks. Extremely weak flow and turnover compared to the least of any modern power filters. I also have run tanks with only air stones or sponge filter run on air. The earliest power filters were also weak by comparison to modern equipment and lost prime very often.
Guess my answer is any flow /turnover rate can work. I think one of the more modern terms is become "polishing" the water when it comes to mechanical filtration. I suppose the lowest flow/turnover rate which keeps the visible stuff cleared out of the water is the minimum.
Good luck

 

[duanes]

There is no such thing as over filtration.
There "is" such a thing as too much flow.
These filter company rate ratios, are BS
I use a 125 gal tank as filtration for a 180 gal, with a 1500gph pump,

and add an 800 gph power head to the main tank to mimic a riverine flow

Of course neither pump puts out the amount they say it does, so flows need to be taken with a grain of salt.
And this goes double for manufactured "all in one" filters.
That said, C.dimerus can come from a variety of habitats, although considered riverine.
In a tank as small as a 29, you won't need much flow.
I kept mine in a fairly strong flow environment, with rock and wood pieces to allow lower flow spots.
Although they aren't a particularly a large or aggressive cichlid, the 29 may not be sufficient as adults to maintain pair compatibility.

I grew my Bella Union variants out in a room temp 60 gal, then moved them to a much larger tank as adults.
Took about 1 year to go from 1 inch, to the size above

 

[jjohnwm]

Agree with all above^. Saying that a tank is "overfiltered" implies that there is some hard-and-fast rule that determiines what is adequate; even if there were (and there isn't) it certainly could not be determined by simply calculating the ratio of water flow rate to tank volume as you have done here and as is often parrotted over and over in the aquarium hobby nowadays.

Take two identically sized tanks; equip each a sump, and with identical pumps that have identical flow rates...doesn't even matter what the actual numbers are. In tank #1, set the sump up so that the entire flow of the pump is going through a single small piece of foam. In tank #2, use several sheets or blocks of foam, filling all the remaining space with K1, ceramic rings, whatever. Tank 2 will have a total biofiltration medium volume many times that of Tank 1, although the flow rate through both tanks is identical. Are those tanks equally filtered or "overfiltered" or "underfiltered"?

How about mechanical filtration? Set up Tank 1 so that all the flow is channeled through a 4 x 4 inch opening, giving you 16 square inches of surface area. Set up Tank 2 so that same flow rate is channeled through a foam sheet that spans the width and height of the sump, like a Matten filter. Far more surface area to trap debris...but the flow rate is the same, so I guess the two tanks are equally filtered...right? No!

When you buy a power filter that is marked on the box "For up to 100 gallon aquariums"...how do you think that number is ascertained? By some arcane and complicated calculation that takes into account mechanical filtration surface area, biofilter volume, tank stocking, water parameters including dissolved oxygen levels and a host of other variables? Fat chance! The marketing guys sit down and say "Well, we've pretty much conned the world into believing that tank volume needs to "turn over" X times per hour for a tank to be successful...and we can probably claim Y gph flow rate for this filter, because nobody will ever check and if they do we will chalk up any discrepancy to "variables" which, again, nobody can measure or control...so simple math lets us get away with claiming this filter will take care of a tank of Z gallons. Done! It's Miller Time!"

You don't "need" filters at all; they're a luxury item that makes fish keeping easier and allows for higher stocking volumes, but they aren't a necessity for keeping aquariums. Neither are calculators.

 

[Hybridfish7]

There is no such thing as over filtration.
There "is" such a thing as too much flow.
These filter company rate ratios, are BS
I use a 125 gal tank as filtration for a 180 gal, with a 1500gph pump,
View attachment 1509461
and add an 800 gph power head to the main tank to mimic a riverine flow
View attachment 1509462
Of course neither pump puts out the amount they say it does, so flows need to be taken with a grain of salt.
And this goes double for manufactured "all in one" filters.
That said, C.dimerus can come from a variety of habitats, although considered riverine.
In a tank as small as a 29, you won't need much flow.
I kept mine in a fairly strong flow environment, with rock and wood pieces to allow lower flow spots.
Although they aren't a particularly a large or aggressive cichlid, the 29 may not be sufficient as adults to maintain pair compatibility.
View attachment 1509463View attachment 1509464
I grew my Bella Union variants out in a room temp 60 gal, then moved them to a much larger tank as adults.
Took about 1 year to go from 1 inch, to the size above
View attachment 1509466

Side note, what was room temp for you? I currently have mine unheated, and haven't seen them come out in a week. Room temp for me is currently in the high 60s.

 

[duanes]

I agree with the above, and.,
When a company rates a filter for let's say a 40 gal tank......they expect it to be stocked with some guppies and a gourami, or some neons and a betta,
or maybe an angel and some barbs.
They are not rating a can, or a HOB for someone serious about keeping cichlids, or bichirs, much less the size tank required for the kind of fish normally kept on MFK, tiger fish, gars or rays.

I had a 50 gal tank in my bathroom, for growing out juvie cichlids, or to be used as quarantine.
Because it wasn't attached to my sump system, I put 3 HOB filters on the back wall, and would rinse 1 filter pad per day

For me, room temp might range from mid 60sF in winter, to mid 70sFto 80 in summer.

I also put the dimerus outside in a pond in Wi from late May to Oct where temps dropped even more, in spring and late fall.

 

[Hybridfish7]

I agree with the above, and.,
When a company rates a filter for let's say a 40 gal tank......they expect it to be stocked with some guppies and a gourami, or some neons and a betta,
or maybe an angel and some barbs.
They are not rating a can, or a HOB for someone serious about keeping cichlids, or bichirs, much less the size tank required for the kind of fish normally kept on MFK, tiger fish, gars or rays.

I had a 50 gal tank in my bathroom, for growing out juvie cichlids, or to be used as quarantine.
Because it wasn't attached to my sump system, I put 3 HOB filters on the back wall, and would rinse 1 filter pad per day

For me, room temp might range from mid 60sF in winter, to mid 70sFto 80 in summer.
View attachment 1509483
I also put the dimerus outside in a pond in Wi from late May to Oct where temps dropped even more, in spring and late fall.

Strange, maybe they're just settling into the tank then. Mine are the paso de la cruz ones.

 

[jjohnwm]

I had a 50 gal tank in my bathroom...

This, ladies and gentlemen...is hard-core...

 

[Azedenkae]

What's a good goal to shoot for in terms of overfiltration? As my current plans stand, my lowest filtration to tank volume ratio will be 1.5:1. My highest will be 12.5:1, inbetweens being 3.25:1 and 10:1. I feel like the 1.5 is too low for my liking, even though it's a 29 with a pair of cichlasoma dimerus.

Not sure what the numbers you are referring for means, but anyways a good goal to shoot for for overfiltration is 4ppm ammonia/day consumption rate, though some people do try for 8ppm.

 

[fishdance]

Doesn't everyone have a tank (or two) in the bathroom?
I also put a toilet in my fish shed. Didn't want to waste space as that means less tanks.