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domjd05
10-21-2010, 06:24 PM
Which is better for plants? Why?

From what I have read:


Micro bubbles work better but are inefficient and some people don't like the bubbles on plants.

Dissolved is much more stable/efficient. But plants seem to utilize the bubbles more efficiently.

I personally like the look of the bubbles on the plants and in the tank. But I've always been told dissolved works better.

I think its safe to say people have used both with good results.

What do you think? What can you say from experience?

funkman262
10-21-2010, 07:47 PM
Micro bubbles work better but are inefficient and some people don't like the bubbles on plants.

Dissolved is much more stable/efficient. But plants seem to utilize the bubbles more efficiently.

I'm sorry, but if micro bubbles work better, how are they inefficient? Seems like some contradictory information to me. Please explain.

Also, do you know why people suggest that plants can utilize bubbles more efficently that dissolved co2? I've never heard that before.

domjd05
10-21-2010, 08:29 PM
I should clarify that I'm mostly repeating what I've heard elsewhere... But I'll try to explain.

Micro bubbles might be described as inefficient because a majority of them will rise to the surface. Undissolved.
They would be more effective however (again this is just what I've heard elsewhere), when sayy for instance they are trapped underneath leaves or something like that.

This would make them inefficient- yet effective. Think big block V8's- guzzling gallons of gas, but hauling a very heavy load up a hill. Inefficient, yet effective. Get it?

Not according to me, but other aquarists- do claim that its harder to maintain a constant c02 level using micro bubbles.

I don't know why someone would say a micro bubble is more effective than dissolved c02. That's why I started the thread- to get opinions on it.

Lady Hobbs
10-21-2010, 10:05 PM
All I can say is that the glass diffusers are supposed to work the best and they put out micro bubbles that are so fine you can barely see it.

smaug
10-22-2010, 12:43 AM
If you see a bubble make it the whole way to the surface it has not given up its gasses to the water colums.Micro bubbles being much smaller and many more of them will transfer there contents to the water column at a much faster rate then big fat bubbles that zip right to the surface.Thus microbubbles create more dissolved co2.A good diffuser as LH states will put get the co2 to the water showing very few bubbles but more of a fine smoke appearance just at the diffuser.

domjd05
10-22-2010, 01:25 AM
exactly, but how does this rate to an inline reactor to which almost NO bubbles are released?

Do the plants want the co2 dissolved or in bubble form? or does it matter?

rich311k
10-22-2010, 01:33 AM
If it is in bubble form it is not dissolved. I believe what you mean is a spray that looks like a mist can be very effective as it spreads the CO2 about the aquarium. To be truly effective those bubbles need to go into solution before they hit the surface. The more surface area there is, IE tiny bubbles the faster the CO2 will dissolve.

An inline reactor with 100% absorption rate will do a nice job of growing plants for you and there is less clutter in the tank.

I think any method that keeps CO2 above 30ppm is effective does not matter what it is.

funkman262
10-22-2010, 02:00 AM
domjd05, if I understand correctly, I think what you're suggesting (strictly based on what you've heard, not personal opinion) is that possibly, plants can more effectively absorb the CO2 if it's left in gaseous form (micro-bubbles) opposed to aqueous form (dissolved). That's very interesting. Plants that are grown emersed (out of water) uptake gaseous CO2 for obvious reasons. I wonder if most aquatic plants have completely evolved away from that method or if they still prefer uptake via gas molecules...

domjd05
10-22-2010, 01:37 PM
Funkman, that's exactly what I'm talking about. I personally have used both with good results, however I can get good results using half the co2 with the dissolved method- with the same if not more amount of pearling. Growth is roughly the same, I'd say its a bit too early to tell.

I was just curious what makes some people think microbubbles are more effective than dissolved- what are they doing that the rest of us aren't? Or are they just backing up their way of doing things regardless of research?

smaug
10-22-2010, 10:01 PM
Its simple science.Smaller bubbles means that whatever is in the bubble is more rapidly absorbed into the water.The bubble simply carries whatever gas is in it to the surface where it pops and goes into the air without the plants ever having used it.

funkman262
10-22-2010, 11:10 PM
Its simple science.Smaller bubbles means that whatever is in the bubble is more rapidly absorbed into the water.The bubble simply carries whatever gas is in it to the surface where it pops and goes into the air without the plants ever having used it.

I don't think that's what the question is about. In the original post, it was explained that while micro-bubbles are less efficient at raising the CO2 level because they're not dissolved in the water, they're possibly more effective for plant growth. So basically, the question is whether aquatic plants prefer CO2 in gaseous or aqueous form.

domjd05
10-23-2010, 01:01 AM
Yep, that is the question.. it seemed kinda vague to even me at the time I was originally typing the first post, sorry for not being more concise.

I'm beginning to agree with what rich said, it doesn't matter, as long as the plants are getting co2.

smaug
10-23-2010, 01:53 AM
I think I answered that very well,as did a few others.