Sunday, March 29, 2009

Boyu CD-01 inline CO2 diffuser

I just bought Boyu inline CO2 diffuser. It can be use inside and outside tank. Just take out the strainer if you want to use it outside the tank. I heard it is very efficient and maintenance free. Not sure how true it is. My guess is brown algae probably will grow inside after a while.

I bought 2 of them from ebay, since none of the local fish shop carry this product. They do have similar product from ISTA but very expensive $27. It cost me S$8.60 for 2 but the delivery charges is S$11.90 which is more expensive than the product. The stamp duty on the mail is only HK$19.1 or S$3.75. Nevertheless, it is still cheaper than ISTA.

I like this product. For starter, it does not reduce the filter flow. Furthermore, I not need to worry about green spot algae. Probably because it is inside cabinet thus no light. However, after a while I can see some brown thing build up (diatome?). It is the same build up that normally hapen inside filter hose. Nothing to be worry about just use brush and clean it during regular filter maintenace. It is much easier to clean compare to green spot algae.


  1. hi,
    any update on these yet.

  2. Hi Robert,

    Im interested on your Boyu CD01, How is the efficiency? Since you have bought 2, and Provided that if you are not using both of them, is that possible that you sell 1 to me?

    My email is


  3. Just update it with my opinion about the product.

  4. sorry Danny, it is prety good product not thinking of let it go.... :p

  5. Why not just put the CO2 tubing into the filter inlet ? It's very efficient too, free and cleaning free ;)

  6. because it can cause airlock, motor overheat and then spoil the filter.

  7. May I know how do you connect this as a externally to the caniester filter and do I need to fill it up with water via the co2 inlet of the diffuser?

  8. very straight forward, there is a drawing on the box on how to connect it to your filter. By the way it does not work with hand on back nor top filter.

  9. just got this diffusor!
    hopefully can have some good result soon

  10. Hi Robert,
    Bought the product after your review and reading AQ forum. the diagram says it should be part of the inlet to the Canister, how close it can be to the canister-inlet ? if one needs to hide it in the cabinet it need to be very close to the Canister-Inlet, will this cause issues with Canister's efficiency.
    G.Senthil Kumar

  11. Hi Robert,

    Can i ask for this Boyu inline CO2 diffuser. There should not be any water in the container right? Am i right to say that water is just passing through it?

  12. Sorry been away from my blog.

    I try both, onw tank attached on inlet and second tank attached on outlet. I do afraid that the one attached to inlet will cause an airlock, so I put prety far away from the canister.

    The will be water in the container when the CO2 is off. It is due to back flow from the canister. Just make sure you put couple of good guality check valve.