Low C02

[kenneth_kpe]

i just got a PH and KH test earlier just out of curiosity and upon doing the test i found out that i only got roughly 6-9 ppm of c02!! kinda low ( just proves to show that airstone diffusion really isnt that efficient, given the bundle that im using a HOB hahaha

btw does anybody know if there is a difference when measuring C02 and night and at day ? also i used sera ph kh test kits, are they reliable ?

anybody got ideas on how i can diffuse the c02 better ? or should i just double my c02 tank and increase my bubbles per minute ? hmmmm

 

[Lateral Line]

You need to keep the CO2 in contact with the water for longer. A bubble type difuser is not much use as the CO2 mostly escapes at the surface. Try feeding the CO2 into an upturned cup or similar so the cup is allways full of CO2.

HOB's tend to agitate the water surface a lot which will help any disolved CO2 to come out of solution.

Plants use less/no CO2 when it is dark. You'd expect, all other things being equal, the CO2 concentration to be igher at night then during photosynthesis. How much depends on what plants, how many of them and the light level.

 

[kenneth_kpe]

OMG!! super fast reply !! i was just about to edit my first post ! i was gonna try the upturned cup and see if it is better, also i cant replace the HOB, external canister filters are really expensive and i find it kinda impracitcal for a 15g, doesnt add up...(thats IMO) i was also just wondering, whats the minimum LPH or GPH should i look for when making a c02 reactor ? im refering to the powerhead that is. ( i have a small 15g tank.

 

[Bangin]

The hang on back filter basically makes CO2 injection useless. I know from experience. It disturbs the surface far too much.

You could try the bell diffuser (run a search on this forum), or even a Hagen ladder would work well.

Edit: You responded just before I did! I wouldn't worry about the powerhead's GPH. I think my reactor came with a Rio pump.

 

[Waterloo Kid]

I recently started using a DIY CO2 setup in my Rio 400. I have the CO2 entering the tank via an airstone and the bubbles rise into the output flow of the standard Juwel filter. The bubbles are blown down into the tank so I'm guessing at twice to three times the contact time of the CO2 and water. My KH is pretty low at 4 degrees so with that simple setup the CO2 has risen from approx. 9ppm to approx 20ppm. The pH has dropped to 6.8 which is perfect for my crowd! Plants have kicked off too. In my case the airstone diffusion has worked well.

WK

 

[kenneth_kpe]

i guess waterloo's tank just goes to prove that it all depends on the setup of your tank. Maybe im gonna try the bell method and then check my levels again, and if that doesn't work im gonna try and minimize the current that is beeing caused by my HOB, any of you guys have an idea on how i can do that ??? .... and if that still doesn;t work im gonna buy a small powerhead and make a reactor.