Interesting experiment
Planted Tank Forums
Your Tanks Image Hosting *Tank Tracker * Plant Profiles Fish Profiles Planted Tank Guide Photo Gallery Articles

Go Back   The Planted Tank Forum > Specific Aspects of a Planted Tank > Fertilizers and Water Parameters


Reply
 
Thread Tools Display Modes
Old 11-12-2012, 04:31 PM   #1
ptr
Planted Tank Obsessed
 
ptr's Avatar
 
PTrader: (21/100%)
Join Date: Sep 2011
Location: NYC
Posts: 462
Default

Interesting experiment


Hi,

The video below shows an experiment with a sponge filter, where the big air bubbles are being spliced into thousands of tiny bubbles by a small Koralia circulation pump. The (possibly stupid) idea is that, there is 0.04% co2 in the air, which means the equivalent of 1 bubble every 2500 (of course the gases are mixed, but you get the idea). With the sponge filter pumping at least 10 huge bubbles per second, it means the equivalent of one huge co2 bubble every 4 mn. Not spectacular, but still, every little bit counts... and as you can see, there is no sign of algae, and all the plants are thriving, even the blyxa.... whereas in my other tank, that doesn't have the same system, plants are having a much harder time.

http://youtu.be/7rDw2VOpFHQ

So what do you experts think ? Am I just being lucky, or is this indeed getting some more CO2 into the tank ?
ptr is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 11-12-2012, 04:38 PM   #2
acitydweller
ओं मणिपद्मे हूं
 
acitydweller's Avatar
 
PTrader: (174/100%)
Join Date: Dec 2011
Location: New York
Posts: 7,659
Default

hmm id give it a shot though its likely less potent than direct co2 injection
__________________
acitydweller is offline   Reply With Quote
Old 11-12-2012, 04:41 PM   #3
ptr
Planted Tank Obsessed
 
ptr's Avatar
 
PTrader: (21/100%)
Join Date: Sep 2011
Location: NYC
Posts: 462
Default

Well yes, especially if you're talking about pressurized. But it would be pretty cool if it could be a viable alternative to yeast-based methods.
ptr is offline   Reply With Quote
Old 11-12-2012, 04:41 PM   #4
KrazyFish
Planted Tank Obsessed
 
KrazyFish's Avatar
 
PTrader: (0/0%)
Join Date: Dec 2010
Location: Binbrook, Ontario, Canada
Posts: 427
Default

Oxygen diffuses into water much easier than CO2, so being that you are only injecting ambient air into the tank, the majority of the surface area in contact with the air is being used to absorb o2 with vary lilttle contact with CO2. Also, you may actually be causing more CO2 to offgas the tank by causing turbulance at the surface.

Anyway regardless of the true results, I personally would not like to see all the bubbles floating throughout my tank. It looks ugly to me.
KrazyFish is offline   Reply With Quote
Old 11-12-2012, 04:45 PM   #5
mstamper
Algae Grower
 
PTrader: (0/0%)
Join Date: Jun 2012
Location: Duluth, GA
Posts: 97
Default

I'm not an expert in any form regarding CO2.
IMO breaking up the bubbles from several larger ones to several smaller ones is just wasting electricity to run the Koralia.

I can see some points for the argument that smaller bubbles of the gasses coming from the sponge filter creates a bigger diffusion similar to using an air stone with a CO2 system but I don't think you are adding any NEW CO2 to the mix, just making smaller AIR bubbles. Yes, there is some CO2 in AIR but you will not be adding any additional CO2 by what you are doing currently.
mstamper is offline   Reply With Quote
Old 11-12-2012, 04:48 PM   #6
ptr
Planted Tank Obsessed
 
ptr's Avatar
 
PTrader: (21/100%)
Join Date: Sep 2011
Location: NYC
Posts: 462
Default

Well I would be running the koralia anyway for circulation in the tank. It's simply about its positioning (right above the sponge filter).
ptr is offline   Reply With Quote
Old 11-12-2012, 05:02 PM   #7
mstamper
Algae Grower
 
PTrader: (0/0%)
Join Date: Jun 2012
Location: Duluth, GA
Posts: 97
Default

PTR,
Sorry, was a bit confused about the use of the Koralia pump. I took it that the entire reason for the pump was to just break up the bubbles coming from the sponge filter.

I'm just wondering, what is your reasoning for increasing circulation over increasing filtration?

I run a sponge filter and a Rena XP2 canister in a 40b and it is almost too much circulation in that tank. I have another 44 hex tall tank that I keep angles in and I have to turn down the penn plax 700 canister output to not blow out the angels with too much circulation and I run a sponge as well on that tank to increase filtration as I do not feel that I am getting enough water exchange with the restricted flow I have set up on that tank.
I personally, could not see adding more circulation but do like having the extra filtration on the cheap.
mstamper is offline   Reply With Quote
Old 11-12-2012, 05:07 PM   #8
ptr
Planted Tank Obsessed
 
ptr's Avatar
 
PTrader: (21/100%)
Join Date: Sep 2011
Location: NYC
Posts: 462
Default

The tank (a 60g tall) also has an aquaclear 110 so there's really plenty of filtration. However, without the Koralia there are a still a few dead spots, hence the additional circulation.

Maybe the tank is just healthy because of the heavy oxygenation.
ptr is offline   Reply With Quote
Old 11-12-2012, 05:48 PM   #9
Hoppy
Planted Tank Guru
 
Hoppy's Avatar
 
PTrader: (74/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 18,638
Default

Quote:
Originally Posted by KrazyFish View Post
Oxygen diffuses into water much easier than CO2, so being that you are only injecting ambient air into the tank, the majority of the surface area in contact with the air is being used to absorb o2 with vary lilttle contact with CO2. Also, you may actually be causing more CO2 to offgas the tank by causing turbulance at the surface.

Anyway regardless of the true results, I personally would not like to see all the bubbles floating throughout my tank. It looks ugly to me.
Actually, that is a bit backward. CO2 dissolves into water much easier than O2 does, and it also comes out of solution equally easy. So, this method does speed up the absorption of atmospheric CO2 into the water, but it also speeds up the loss of CO2 to the air, due to the water surface disturbance from the bubbles. So, you will get no net gain in CO2, above what you get with a quiet water surface, but you are probably getting more of the CO2 down into the lower water to replace that used by the plants. Just good water circulation in the tank will do that too. If you don't like seeing those bubbles, just using the Koralia to keep the tank water moving will do the same job.
__________________
Hoppy
Hoppy is offline   Reply With Quote
Old 11-12-2012, 05:59 PM   #10
ptr
Planted Tank Obsessed
 
ptr's Avatar
 
PTrader: (21/100%)
Join Date: Sep 2011
Location: NYC
Posts: 462
Default

Well actually, you get less surface disturbance compared to having the sponge filter on its own, since most of the bigger bubbles don't get a chance to reach the surface.
ptr is offline   Reply With Quote
Old 11-12-2012, 06:28 PM   #11
KrazyFish
Planted Tank Obsessed
 
KrazyFish's Avatar
 
PTrader: (0/0%)
Join Date: Dec 2010
Location: Binbrook, Ontario, Canada
Posts: 427
Default

Quote:
Originally Posted by Hoppy View Post
Actually, that is a bit backward. CO2 dissolves into water much easier than O2 does, and it also comes out of solution equally easy. So, this method does speed up the absorption of atmospheric CO2 into the water, but it also speeds up the loss of CO2 to the air, due to the water surface disturbance from the bubbles. So, you will get no net gain in CO2, above what you get with a quiet water surface, but you are probably getting more of the CO2 down into the lower water to replace that used by the plants. Just good water circulation in the tank will do that too. If you don't like seeing those bubbles, just using the Koralia to keep the tank water moving will do the same job.

Hoppy, thanks for setting me straight. I guess I misinterpreted something I read in the past.

One thing though, if an aquarium were getting its CO2 from only atmospheric exposure (ie, surface exchange and bubbles from an air pump), would the gain and the loss not be pretty much equal?
KrazyFish is offline   Reply With Quote
Old 11-12-2012, 11:37 PM   #12
Diana
Planted Tank Guru
 
PTrader: (0/0%)
Join Date: Jan 2010
Location: Contra Costa CA
Posts: 6,847
Default

Quote:
One thing though, if an aquarium were getting its CO2 from only atmospheric exposure (ie, surface exchange and bubbles from an air pump), would the gain and the loss not be pretty much equal?
Almost none of the gas in large bubbles end up in the water. The large bubbles burst at the surface of the tank. As these bubbles rise they are dragging some water with them, bringing it to the surface, improving the vertical water movement. The turbulence of the large bubbles bursting at the surface is also increasing the surface area of the water, so more gas exchange is happening for 2 reasons:
a) CO2 depleted water from lower in the tank is being brought to the surface.
b) larger surface area.

So, comparing 'no water movement' to 'large bubbles' there is a net increase in CO2 for the plants.
But in this tank there is already quite a bit of water movement from the filters. So the increase in vertical water movement may not be needed.

When the bubbles are being broken up this way, the Koralia is chopping them into little bubblets (if there is such a word) AND is sending them horizontally through the tank.

100 little bubblets have more surface area than one giant bubble, so there may actually be some gas exchange happening while those bubblets are in the water.
Also, little bubblets may stay submerged longer. Maybe not a lot longer, but some may be getting caught under the leaves and so on. The whole bubblet might end up disappearing!

I am not sure how tons of little bubblets compare to the same volume of large bubbles when it comes to surface agitation. If each bubblet creates a 1mm wavelet, but each giant bubble creates a 5mm wavelet plus some splash... but there are a lot more little bubblets...
Diana is offline   Reply With Quote
Old 11-13-2012, 12:26 AM   #13
ptr
Planted Tank Obsessed
 
ptr's Avatar
 
PTrader: (21/100%)
Join Date: Sep 2011
Location: NYC
Posts: 462
Default

In my case, I have observed a better growth, less algae, and overall better plant health with this setup. I would love to have other TPT users try the same thing and post their results.
ptr is offline   Reply With Quote
Old 11-13-2012, 01:15 AM   #14
chibikaie
Planted Tank Enthusiast
 
PTrader: (6/100%)
Join Date: Aug 2012
Location: Connecticut
Posts: 561
Default

Ooooh, this does look neat. I might have to try this, although arguably my goldfish tank needs more filtration as well as circulation.
chibikaie is offline   Reply With Quote
Old 11-14-2012, 02:15 AM   #15
Gold Finger
Planted Tank Enthusiast
 
Gold Finger's Avatar
 
PTrader: (0/0%)
Join Date: Oct 2011
Location: Wpg. MB Canada
Posts: 819
Default

Yes, interesting. Not stupid. I believe you are getting more net CO2 and, perhaps more importantly, more O2 into your water. Get the bubbles small enough (microbubbles) and everything will enter the water. It may not be a lot of CO2, maybe even a completely negligible amount, but it seems to me like it should be some amount higher than you would get atmospherically from a turbulence source. Maybe you are right, but higher O2 is my guess as to any true connection to less algae there may be. Having a non CO2 tank, I used to give this stuff a lot of thought. I settled on having all of my tank water leave the tank and go to the sump through surface skimming. This way the surface exchange membrane a) is always spottless and therefore as permeable as possible, and b) is moved back into circulation and quickly replaced with fresh, CO2 hungry water from below. Perhaps it is moot for me now as I am using Excel, but perhaps not. Any advance in higher CO2 levels for non injected tanks is a good thing. Interesting in any case.
__________________
Ver. 1.0 80 gallon dirt goldfish tank (defunct)

Ver. 2.0 bare bottom same tank another approach (defunct)

Ver. 3.0 Pool filter sand same tank now

Farming Algae

Goldfish are among the worst fish for beginners.
Gold Finger is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 02:58 PM.


Powered by vBulletin®
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright Planted Tank LLC 2012