Medium CO2 levels. Algae? - The Planted Tank Forum
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 12-01-2016, 05:52 PM Thread Starter
Algae Grower
PTrader: (0/0%)
Join Date: Oct 2016
Location: Finland
Posts: 41
Medium CO2 levels. Algae?

Most sources seems to suggest that when CO2 is added, the target should be 30ppm.
Only source I can come up that is even speaking of using medium values such as 10ppm is Tropica that list that value as target for their Medium category plants. And they say that adding at least some CO2 will make a huge difference.

Tom Barr seems to suggest that 5-10ppm is not good, since it might cause algae.

So the questions:
- Is there a concensus for the Tom Barr's claim
- What is the CO2 level of a regular low tech medium stocked tank that has no CO2 injection? I know some sources say falsely that it is 7ppm, some say that equilibrium is about 0.5ppm and forgot that decaying stuff makes it a bit higher. But how much higher?

The reason I'm asking is that I'm buying the Tropica claim that even a little addition is really good and so I would like to add a little CO2. But I do not wan't to run into algae issues. And I do not want the full hasle of a high tech setup.

So if I aim at 5-10ppm, am I doing something stupid?
nikohak is offline  
Sponsored Links
post #2 of 6 (permalink) Old 12-01-2016, 07:01 PM
Planted Tank Obsessed
SwissCheeseHead's Avatar
PTrader: (1/100%)
Join Date: Dec 2014
Location: Madison, WI
Posts: 452
See @Hoppy's thread:

I try to run 1-1.5 bps with my CO2 setup and have seen BBA reduced greatly. I have a little bit on the lace plant that is very close to the light. I still deal with GSA on the glass but not on the plants. Just physical removal for that stuff.

Love your tanks and they will love you back
SwissCheeseHead is offline  
post #3 of 6 (permalink) Old 12-01-2016, 11:03 PM
Planted Tank Enthusiast
PTrader: (2/100%)
Join Date: Oct 2012
Location: California
Posts: 890
The reason you aim for a higher concentration of CO2 is because the concentration of CO2 in different parts of the tank varies. IF you aim for 5-10 ppm then you have a chance that the CO2 in certain parts of the tank could be lower or 0 ppm of CO2. If you aim for a higher concentration then this could ensure higher concentrations in other parts of the tank.

This is the reason why good circulation is important.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
PortalMasteryRy is offline  
post #4 of 6 (permalink) Old 12-02-2016, 02:43 AM Thread Starter
Algae Grower
PTrader: (0/0%)
Join Date: Oct 2016
Location: Finland
Posts: 41
That link Swisscheesehead gave was a really good read even if it did not contain any definitive answers.

It seems, by looking the Hoppy's graph, that in low light setup, the plant growth varies dramatically even with small co2 changes when the concentration is less than 10 ppm. And I am going to guess that fluctuation leads to problems with plants and that in turn leads to algae bloom. And that same 10ppm is also the upper limit that Tom Barr suggested for optimal algae growth. So based on these, I think that I will aim to CO2 at 10-15ppm when lights go off. So then CO2 is not the limiting factor and fluctuations should not affect the plant growth. And I should have good flow with over 10x the tank volume per hour so the concentration should be fairly even. I just need to keep lights low.

I believe also in high tech tanks many have gotten rid of algae problems after pushing the CO2 past the 30ppm mark that was the point where CO2 changes stopped affecting plant growth in Hoppy's graph. That would support my "theory" also.

Or that I do what Swisscheesekake is doing and add so trivial CO2 that it helps the plants some, but is always so little that plants know how to build their "production lines". So no fluctuations between having limiting and unlimiting CO2.

Last edited by Darkblade48; 12-02-2016 at 10:46 AM. Reason: Please use the edit function for back to back posts to keep threads cleaner
nikohak is offline  
post #5 of 6 (permalink) Old 12-02-2016, 11:07 AM
PTrader: (4/100%)
Join Date: Nov 2013
Location: Near Ashville, North Carolina
Posts: 1,866
Tom Barr only says that low co2 with high light equals algae. At low light hoppy is correct that it can be beneficial without causing algae.

Sent from my XT1585 using Tapatalk
jrill is offline  
post #6 of 6 (permalink) Old 12-02-2016, 02:40 PM Thread Starter
Algae Grower
PTrader: (0/0%)
Join Date: Oct 2016
Location: Finland
Posts: 41
I was referring on Tom Barr saying that algae grows best at 5-10ppm. I don't know what that means exactly. You can find that on the link in my first post.
nikohak is offline  


Quick Reply

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome