Eheim oxygen diffusor?

mchambers

Former CCA member
Anyone use this? I bought and installed one recently. Basically, it takes the place of a spray bar. It channels the water output through a narrow channel, so that the water comes out with fairly high force. It also has an airline attached, so that air is sucked into the filter output (using the Venturi effect also used by water changers), resulting in lots of small bubbles in the water.

There's a lengthy discussion of the use of the diffusor at

http://www.fmueller.com/home/aquaristic/125g/technology/aeration/

Surprisingly, there isn't much discussion about this device on the Internet, other than the discussion linked above and postings by the same person at another forum.

So far, I'm happy with the diffusor, but can't really be sure if it's good for the fish. It clearly isn't for all fish, with the jet of water and increased forcefulness of the water flow.
 

Avatar

Plenipotentiary-at-large
Doubtless good for fast-water fish

Most powerheads have the same option with plastic tubing that ports in and similarly uses flow to suck/mix air into the output stream, can't say about the virtues of this but it's a nice effect. One could probably adapt a spay-bar to do the same thing by removing the end-cap, taping over all the ports but one and similarly using a piece of tubing - might require some angling on the tubing cut/insertion to create the desired suction so that it doesn't just spray water instead....

Don't you just love $10-$20 pieces of mass-produced plastic? For all the virtues of their products (at least formerly) Eheim seems to have made this something of an art form. Woe be to anyone that buys a used Eheim filter without the tubing/attachments/media and discovers that they're looking at $100+ to replace with original components.
 

dogofwar

CCA Members
Same - that's not just any plastic...it's German plastic.



Don't you just love $10-$20 pieces of mass-produced plastic? For all the virtues of their products (at least formerly) Eheim seems to have made this something of an art form. Woe be to anyone that buys a used Eheim filter without the tubing/attachments/media and discovers that they're looking at $100+ to replace with original components.
 

MarkK

Administrator
Staff member
What does it matter if there are bubbles in the water?

When I was a kid, all the aquarium books (and I read every one I could get my hands on) said that the surface area of a tank was the key factor in how many fish a tank could support versus the sheer quantity of water. So the argument was that the 50 Gallon tank with footprint of 36X18=648 Sq. In. was superior to the 55 Gallon tank with 48X13=624 Sq. In.

It was said that the surface area is where gaseous exchange took place, and the more surface area the better. The argument continued that any kind of aeration/agitation of the surface increased the surface area and therefore increased gaseous exchange.

I don't know if these theories still hold or if they have been overcome by current thinking. Obviously the key factor of current aqua keeping is the nitrogen cycle with partial water changes to reduce Nitrates while when I was a kid we added water to make up for evaporation, and we did partial water changes to reduce the buildup of salts and minerals in the water, without regard for the Nitrogen cycle.

I had times when the water level dropped so low in my tanks that the siphon feeding the Supreme Aquamaster pump stopped, so I just unplugged the filter until I got around to doing a water change!

My father suggested I leave the de-chlorinator out of the water when doing partial changes--he thought the chlorine might kill the evil bacteria!!!

So my point is that we just do not know what effect these kinds of devices have on our tanks or our finned friends.

However, it is lots of fun to tinker with the tanks, the setups, to add gadgets and tinker with them, so it can't hurt.

I think we do know that we need current in the tank, to evenly heat the tank, to circulate whatever oxygenated water we have, so it probably does not matter what method we use ranging from a simple air stone in a sunken ship to your venturi system, to power heads or simple air driven sponge filters.

Without scientific experiments with adequate control groups it boils down to anecdotal experience, your own and others'.

It is all a matter of personal preference, what we stumble upon at the various auctions, shows and LFS's.

That being said, in the words of my own internist when I asked him if I should take the 81mg aspirin daily--"It can't hurt!"
 

Avatar

Plenipotentiary-at-large
No mostly

So my point is that we just do not know what effect these kinds of devices have on our tanks or our finned friends.

Without scientific experiments with adequate control groups it boils down to anecdotal experience, your own and others'.

It is all a matter of personal preference, what we stumble upon at the various auctions, shows and LFS's.

"Anecdotal experience" derived from observation is the basis for most of science and should not be cavalierly dismissed, though it should perhaps be considered in a context of "believe none of what you hear and half of what you see". It is NOT remotely "all a matter of personal preference" because the fact is that some things/approaches work better than others and some things do not work at all. To believe/represent otherwise is naive and misleading to others. This is not to say that there are not many options for achieving the same goals/fulfilling the same requirements, but it's also not as if a hypothetical "personal preference" for allowing god's mercy to purify an aquarium will do the job. I exaggerate, but I believe you can see the point.

Aeration, gas exchange and oxygen are certifiably good things in aquaria, and clearly some methods of achieving this are superior to others, just as the means to ascertain which are available if one cares to do some reading/research. Not everyone is simply "stumbling" through the hobby, and as a great many people have indeed done a great deal of research on almost every conceivable aspect of the hobby, I have to reject the assertion that all hardware and tank management is effectively equal and that everyone is just flying by the seat if their pants. My tanks and techniques aren't bad, but they're far from what they might be and what others manage routinely because of their knowledge, commitment and experience, but moreover, "the ability to judge and think critically" - absent that one can only ever be along for the ride as opposed to actually driving.


"An aquarium is natural selection in a box. Any real evolution however, occurs almost exclusively outside the glass". — Freshwater Paradigms, Chapter 12, Volume 2, Encyclopedia Aquatica
 

dogofwar

CCA Members
Our hobby would certainly benefit from more rigorous, unbiased testing of products and approaches...and less conjecture, theory and one-off observation.

Do the various potions, concoctions, tinctures and other stuff on the market actually work as prescribed? How well does one brand of ich medication work vs. another? Filtration approach (canisters vs. UGFs vs. sponges)? And how about independent analysis of various foods (and their proximity to natural diets for different varieties of fish)?

What I've described is the aquarium equivalent of one of the most contentious aspects of health reform: comparative effectiveness research (now called patient centered outcomes research). It seems that drug companies, device makers...and basically anyone in the healthcare industry doesn't want the effectiveness of their stuff measured against its competition. So funding for such research has (historically) been pretty slim.

The debate between the need for gold-standard clinical trials on everything before we are able to know anything...and the role of the general public (people and patients) making anecdotal conclusions is just as alive and well in medicine as fish stuff. How many people believe Jenny McCarthy (or their aunt) over scientific clinical trials?

That said, there are plenty of "known knowns" about freshwater aquarium keeping.

And there are many myths that persist and multiply (to an even greater scale) because of the internet. My favorite has to do with the role of garden hoses in poisoning fish. What are some of your favorites?

To ramble on a little more:

Wouldn't it be awesome if we could work with kids in say middle school to conduct science fair experiments to answer some of these questions? I remember doing something similar (comparing the growth of anacharis in 10g tanks with ambient sunlight, a florescent light and an incandescent one) in a 7th grade sceince fair. Any middle school teachers or parents in the club who might be interested? Thoughts on how we could piggy-back something that's already going on?

Matt
 

Avatar

Plenipotentiary-at-large
Spawn 'til you die - (Can we do T-shirts of this for AquaMania?)

Mark-

Please forgive the tone of my previous response - think I understand what you were trying to say, there is indeed a lot of "whatever works" in play among aquarists. Fortunately it's a only a little harder to keep things alive than it is to kill them, and generally only slightly more challenging to get them to thrive rather than simply survive which you as a successfully breeder doubtless appreciate.

Samuel
 

dogofwar

CCA Members
AquaMania 2014 (and beyond)!

...unless, of course, we want to have a CCA Kids Science Fair (with prizes) at an upcoming meeting.... (Just an idea!)

Matt

Mark-

Please forgive the tone of my previous response - think I understand what you were trying to say, there is indeed a lot of "whatever works" in play among aquarists. Fortunately it's a only a little harder to keep things alive than it is to kill them, and generally only slightly more challenging to get them to thrive rather than simply survive which you as a successfully breeder doubtless appreciate.

Samuel
 

Avatar

Plenipotentiary-at-large
Jenny who?

Have made a career out of avoiding all vendors/products/services that exalt an individual as much or more than whatever is being offered - same with designer anything, if something has a visible logo on it am not interested (which can make buying good basketball shoes a bit of a challenge).

Hadn't heard the one about garden hoses - still fending off "tank cyclers" "canister cleaners", and the agents of "better living through chemicals". :D

I don't think we should foist it off on the kids - should do our own experiments. In essence we already do, we're mostly just lacking control groups and baselines, but when I don't clean a canister filter in over a year when most of what I'm hearing and reading says "bad to fatal idea", how is that not an experiment? When Christine pressure tests her marriage with the introduction of a worm farm into her happy home, or Tony, et al. with yet another tank/species/CCA commitment, isn't that an experiment? Same with skipping water changes, changing food/feeding schedules, lighting, etc., even changes in who's swimming with whom. (There it is! -theme music for AquaMania - Who's Swimming Who? --http://www.youtube.com/watch?v=1HwF8VoyKU4)

Bottom line is we're all experimenting all the time, we just don't take notes and proceed with sufficiently rigorous methodology to qualify any of it as "science". I think most of the bad "scientists" are self-selecting - the folk who never/rarely spawn anything and whose fishrooms are effectively black holes for flora and fauna that go there to perish. The good scientists or experimenters are the one that manage otherwise, and while they may not know all or the whole truth about anything, they've got a piece of it or they wouldn't have fish routinely showing up at auction.

Like anything else, I suppose one always need to consider the source...

Better than kids' experiments (that soooo sounds just like most of us), I'd be interested in seeing a list of what people think they know to be true (in an aquatic context) that is self-taught on the basis of direct experience - sort of the gospel according to CCA. Have to give it some thought myself (lest my own contribution is wholly without any substance/value whatsoever), and it should probably be a new thread, but I think there's probably a lot of collective knowledge among this group that could be of great benefit if some of it were a little more universal.
 

sundragon

Members
I wonder if this would be a nice way to diffuse CO2. It looks smaller than power heads and being able to hide it means less ugly visible equipment. I use an inline diffuser and inline heater so I have less stuff in the tank.
 

MarkK

Administrator
Staff member
Avatar,

I do agree that there are certain processes that we must follow in order to be successful fish keepers and I do agree that we can learn from others, experience.

But at the same time, there is a random element in terms of what we choose to use, for example I use Emperor and Aqueon HOB filters and sponge filters while someone else may use Fluval HOB filters etc. That was the random element, perhaps I stumbled upon the Aqueon filters and thought they had some nice features while you saw Fluvals (or whatever).

It is just that while it seems to make intuitive sense that the Marineland bio-wheel filter might provide good surface area for nitrifying bacteria, I still have this feeling in the back of my mind that it there has not been adequate controlled experimentation that allows us to really know, which is why I combine HOB filters with internal sponge filters, or on my larger tanks I combine the sponge with a canister.

Anyway, I appreciate everyone's viewpoints.
 

Avatar

Plenipotentiary-at-large
Vested interests

Nothing like selective (psuedo) science and marketing to make it all sound like the best thing since sliced bread.

I found Fluval's recent efforts to promote their line of "C" filters as having "5-stage filtration" very entertaining. After mounting a pre-filter on one I picked up at auction mine is now technically a 6-stage - no idea if it works any better than my numerous ACs but it has very sexy bright red components and all sorts of things to break or go missing - makes me feel like a technician just putting it altogether.

One theory I have developed is that all HOBs made with soft black poly-vinyl or whatever it is eventually warp and become noisy/irreparable whereas filter housings made out of hard clear plastic (like ACs) retain their shape and pretty much last forever. I also greatly prefer to see inside the filter which is after all the crucible/reactor/engine for most of the essential chemistry in the system. If anyone ever makes a decent transparent canister filter am sure I won't be able to resist, especially if it's a cycling type like the Eheim wet/drys.
 
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