Just set up my first DIY CO2 generators - The Planted Tank Forum
 
LinkBack Thread Tools Display Modes
post #1 of 9 (permalink) Old 05-20-2011, 03:41 AM Thread Starter
Wannabe Guru
 
VeeSe's Avatar
 
PTrader: (8/100%)
Join Date: Apr 2011
Location: Richmond, VA
Posts: 1,423
Send a message via AIM to VeeSe Send a message via MSN to VeeSe
Just set up my first DIY CO2 generators

Hey all,

Not too much to say in this post. Just set up my first ever DIY CO2 for my tank. I hope the plants will like it, as I already had too much lighting. I'll continue to dose Excel for a little bit for the first couple of days at least. I'm running an airstone during lights off, although my Aqueon55 is already providing a lot of surface agitation, so I'm not sure my DIY CO2 will have the greatest effect.

Setup for my 55G tank is two 2L bottles, each with 2 cups sugar, 1/4 tsp baking soda, and 1/2 tsp bread machine yeast running to a small water bottle bubble checker then to a check valve and to the Hagen elite mini filter as my diffuser. Not getting a stable bubble count yet because it just got set up less than 3 hours ago, but I'm excited.

I have a drop checker and pH drops but I don't have any 4dKH reference solution yet. My only concern is gassing my fish, but I heard that it's hard to get enough CO2 with DIY to do that, so should I even be worried at all? I'll eventually get around to setting it up, but hopefully it's not too necessary to have right away.

Already thinking about getting into pressurized
VeeSe is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 05-20-2011, 04:39 AM
Planted Tank Guru
 
PTrader: (84/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 21,015
It is very unlikely that you will be able to get enough CO2 that way to bother the fish. I wouldn't worry about it. What lights do you have over the tank?

Hoppy
Hoppy is offline  
post #3 of 9 (permalink) Old 05-20-2011, 04:51 AM Thread Starter
Wannabe Guru
 
VeeSe's Avatar
 
PTrader: (8/100%)
Join Date: Apr 2011
Location: Richmond, VA
Posts: 1,423
Send a message via AIM to VeeSe Send a message via MSN to VeeSe
I've got a standard 48" T5HO 6500K running. It's on one of those mounts with four legs that is a little more than 2" above the top of the tank. I'm hoping that puts it just slightly far enough that I get 60-70mm PAR to the bottom, which I hope isn't too much even for DIY CO2.

edit: checked the chart in the lighting forum sticky. I'm assuming 18-20" from the substrate since the light is 2" over the top of the tank and my substrate is 2-4" high (although the 4" doesn't really bring it back down to 18" since the light isn't directly over the back of the tank, but I guess that's negligible over such a small distance at such a small angle). Too bad I don't have a PAR meter, but I don't think it's that important. I think I probably need even more CO2 than I can get with DIY. Just going by the chart, I'd have 60-80mm PAR
VeeSe is offline  
 
post #4 of 9 (permalink) Old 05-20-2011, 05:46 AM
Planted Tank Enthusiast
 
Bandit1200's Avatar
 
PTrader: (4/100%)
Join Date: Dec 2010
Location: Houston, Texas
Posts: 724
my $.02

using your basic forumula, I was using 3 2L bottles on my 29 gallon to get 30ppm. I kept them rotated so that there was a fresh one every weekend, which gives a 3 week rotation. Had them all tied into a Red Sea 500 and it did a decent job.
Bandit1200 is offline  
post #5 of 9 (permalink) Old 05-20-2011, 05:58 AM Thread Starter
Wannabe Guru
 
VeeSe's Avatar
 
PTrader: (8/100%)
Join Date: Apr 2011
Location: Richmond, VA
Posts: 1,423
Send a message via AIM to VeeSe Send a message via MSN to VeeSe
I haven't siliconed the tops of the caps at all, as the holes seem tight enough with the tube in them (checked for leaks by filling caps with water before setting it up). Should I get some silicone and seal them, or is it not really necessary?

edit: by that math then, if you were using 3x 2L bottles to get 30ppm on your 29g, then I should get approximately 30ppm * (2 bottles/3 bottles) * (29g/55g) = 10.5ppm, but I have some surface agitation with my HOB filter, so I may get less than that.
VeeSe is offline  
post #6 of 9 (permalink) Old 05-20-2011, 07:16 PM
Planted Tank Guru
 
PTrader: (84/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 21,015
Any CO2, above what comes from the air, is good for the plants. I think you will see good results from what you have. And, I don't think your light intensity is high enough that you have to have more CO2 to avoid algae problems.

Hoppy
Hoppy is offline  
post #7 of 9 (permalink) Old 05-20-2011, 11:18 PM Thread Starter
Wannabe Guru
 
VeeSe's Avatar
 
PTrader: (8/100%)
Join Date: Apr 2011
Location: Richmond, VA
Posts: 1,423
Send a message via AIM to VeeSe Send a message via MSN to VeeSe
Quote:
Originally Posted by Hoppy View Post
Any CO2, above what comes from the air, is good for the plants. I think you will see good results from what you have. And, I don't think your light intensity is high enough that you have to have more CO2 to avoid algae problems.
I just measured my pH and it looks like it's 0.5 lower than last night when I initially started the CO2. Since pH is a logarithmic function of H+ ion concentration, I was wondering how we would adjust the 1.0 drop in pH = 30ppm CO2 rule. I'm not sure of the chemistry behind why CO2 causes a drop in pH, so I can't really extrapolate.
VeeSe is offline  
post #8 of 9 (permalink) Old 05-21-2011, 05:34 AM
Wannabe Guru
 
PTrader: (1/100%)
Join Date: Apr 2011
Location: Westfield, IN
Posts: 1,746
Quote:
Originally Posted by VeeSe View Post
I haven't siliconed the tops of the caps at all, as the holes seem tight enough with the tube in them (checked for leaks by filling caps with water before setting it up). Should I get some silicone and seal them, or is it not really necessary?
If it's producing bubbles in the aquarium through whatever you've got diffusing it, it's probably not leaking substantially. I can't seem to get the tubing to seal against any size hole I drill, so I wind up siliconing the stuff in.

As far as the amount of CO2 dissolved in the tank water and the pH change it causes, it's really hard to say. The pH change would depend on the water's chemistry (pH, carbonate content and such.)
jasonpatterson is offline  
post #9 of 9 (permalink) Old 05-21-2011, 04:45 PM
Planted Tank Guru
 
PTrader: (84/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 21,015
Quote:
Originally Posted by VeeSe View Post
I just measured my pH and it looks like it's 0.5 lower than last night when I initially started the CO2. Since pH is a logarithmic function of H+ ion concentration, I was wondering how we would adjust the 1.0 drop in pH = 30ppm CO2 rule. I'm not sure of the chemistry behind why CO2 causes a drop in pH, so I can't really extrapolate.
A pH drop of 1.0 means the ppm of CO2 went up by a factor of 10. A 0.5 drop means it went up by a factor of 3.2. But, unless we know how much CO2 was in the water to start with, there is no way to know what the ppm was after the CO2 was added. The 30 ppm number comes from assuming the tank water started at 3 ppm. But, if it started a 2 ppm you would have 20 ppm.

Hoppy
Hoppy is offline  
Reply

Tags
None

Quick Reply
Message:
Options

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

Password:


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

Email Address:
OR

Log-in










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