Co2 Diy Kit - Tiny Bubbles On Surface

[TUpton98]

Hi All,

I have just installed a DIY Co2 kit (the 2 litre botttle, sugar, yeast etc ) and this links to a Hydorair pump(http/www.aquatics-direct.co.uk/productDetails.asp?productID=2070) which pumps the CO2 into the tank. The pump isn't constant and only pumps the co2 as it is created. There are small jets of tiny little bubbles that disperse into the water every so often, these float up and get moved around with water flow from the the Juwel pump in the filter compartment.

What is happening is that when I look upto the top of tank from the floor I can see 1000's of tiny little bubbles on the surface of the water (due to the lgiht shining through) but cannot see these from looking down.

What I want to know is:

a) Should this happen and the bubbles be on the suface like this? Or is this menaing that the co2 isn;t being diffused correctly?

b) is the Hydor pump not a good idea and should I opt to get a diffuser like this one on eBay (http/cgi.ebay.co.uk/Aquarium-3-Spiro-Glass-CO2-Diffuser-w-Check-Valve-D4_W0QQitemZ160220427733QQihZ006QQcategoryZ20756QQssPageNameZWDVWQQrdZ1QQcmdZVie
wItem)

Finally what c02 ppm levels should I be looking to achieve for a planted tank? I have a Juwel Rio 125 (125 litres)

any advice appreciated.

Terry

 

[aaronnorth]

a) you can never get co2 to dissolve 100% so that is ok.

b) The pump is ok, you won't get much better with a glass diffuser.

c) Aim for 25-35ppm (green colour on a drop checker) you can also check for co2 by measuring the kh then refering to co2 table in my sig.

 

[sjdriscoll]

When CO2 bubbles are very small, which is good, those that don't fully dissolve get trapped in the surface 'film' by surface tension. This is good as they will still dissolve into the water column eventually.

You need a drop checker to test accurately for CO2 or use the 'rougher' method suggested by aaron.

 

[TUpton98]

Thanks for the responces.

Puts my mind to rest. I did a test of PH and KH last night and believe I have roughly 21.4ppm co2 (using an online co2 calculator).

Is there any easier way to test co2 other than measuring both PH and Kh and then working it out from that?

 

[aaronnorth]

Drop checker is only other way i think, you put a few drops of 4DKH solution in to the drop checker then add a couple of drops of ph reagent to make it colour, blue - not enough, green - ok, yellow - too much. You then have to channge the solution weekly and it is a permanent test so you can see how the co2 levels changes through out the week