[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Best CO2 Reactor

Scott Hieber wrote:
"James Purchase pointed out that ADA makes different sizes of diffusers
for different size tanks-- suggesting that that is why an ADA diffuser
might not do as well as other methods of injecting CO2."

Errr, not quite. I questioned Roxanne because in her first posting on the
subject she said that she had an "ADA style" diffusor, and then in a later
posting she said that she had an ADA diffusor. I just want to find out if
she is in fact using a genuine ADA diffusor or if it is one from another
company and she is just reffering to it as a generic name.

I'm concerned that if any device or company is going to be labelled as less
efficient or effective, we all know exactly what is being discussed. Using a
"brand name" as a "generic name" could give some people the wrong
impression. And as we have found out here, wrong impressions can sometimes
lead to lawsuits.

It might seem like a minor point but I think it is an important one - there
_are_ other companies which make diffusers meant for CO2 (ADA even makes
ones for O2 and according to what I have seen and been told, while they look
alike they are not interchangeable). As far as I know, nobody has run any
definative tests to determine which of the many diffusion devices on the
market is more or less efficient than the others. It might be deemed unfair
to one or more companies (and products) to lump them all together under a
generic group. And given the fact that ADA's diffusers come in a variety of
sizes, meant for variously sized aquariums, any honest discussion of their
effectiveness ought to include details of the exact model used and exactly
how it is placed inside the aquarium.

I do know that the different diffusors on the market have different
diameters - my Dupla diffusor is not the same size as the Eheim model I have
and both of them are smaller than the ADA CO2 Beetle 30 which I also have
(and that's not the biggest one that ADA markets). A larger diameter
diffusion disk might allow for more CO2 to get into the water. The disk
material and pore size might also be different in the different diffusors -
that would also effect the efficiency and bubble size.

As has also been pointed out, efficiency is only one factor to consider when
choosing the hardware for CO2 injection (or anything else concerning
aquariums). Just because you can see a few small bubbles reach the water's
surface doesn't mean that you are wasting CO2. The CO2 gas contained in the
"mist" released from a CO2 diffusor will diffuse into the water as the
bubble rises. Some of the escaping CO2 gets replaced in the "bubble" by gas
dissolved in the water - the diffusion is a 2-way street. When the little
bubble hits the air-water interface, it isn't all CO2 inside, there is a
mixture of gases there. Compresssed CO2 is cheap - I don't feel the need to
wring 100% efficiency out of any injection device.

Personally, I don't think that the diffusion devices are the most efficient
way to get CO2 into the water - I really like my Dupla Reactor S. But it was
designed for aquariums over 100 gallons and costs a small fortune (I'm still
amazed that I spent _that_ much for a piece of injection moulded plastic!).
Then again, some of the larger diameter ADA ceramic diffusors are also very
expensive. On the few tanks I have set up which still rely on yeast
generated CO2 fed into Hagen Aqua Clear power filters, the periodic gurgle
of CO2 gas entering the impeller chamber provides an easy check that the
reactor is still producing gas. The fact that I have to pull handfulls of
plants out of these tanks each week tells me that they are efficient enough
for my purposes.

I agree 100% with Scott's comments about time being more valuable than CO2.
If you have multiple tanks and multiple devices that require a lot of
maintenance, the fun can quickly go out of the hobby. But in a relatively
small "display tank", where looks are important, a small handblown glass
device such as those make by ADA certainly would be my preferred choice.

James Purchase