Hi Folks, I'm new to all this and have just purchased the spiro one. I'm having a lot of trouble getting it filled with water though.
Anyway yes the bubbles do seem to come from just one part of the disk and here was me thinking the whole disk would emit the co2
Also I have read on these forums about some having a small hole at the base of the spiral and how everyone thought this was a fault. i don't think it is a fault...should it not be there?
I say this because it is advertised as being used as a bubble counter as well so you would need an area beneath the co2 bubble that is created at the top of the diffuser to show this bubble. The spiral will never be full of water as some might think.
Mines has this small hole in the base of the spiral and although my spiro is only 1/3 full of water, this small hole is under the water level and I can adjust my needle valve by counting the bubbles that escape from it. How else could you use this as a bubble counter if it did not have this pin hole?
So I say these are not faulty and this is how they are manufactured. Mines seems to be working perfectly, despite the difficuty in filling with water.
John