Hi Linda,
You sent me a PM but it seems to have deleted itself from the inbox on these forums. In the thread aaronnorth pointed out you can see i've just taken my ph controller off my jbl setup because frankly the whole thing works better without it. Plus the probe is very annoying to calibrate and setup properly.
Plug the solinoid into a timer which puts the CO2 on for the duration of your lights and your plants will get a more consistant CO2 supply. This will give you a constant supply of CO2 during the part when the plants are using it, then during the night when they absorb O2 and give off CO2 you dont over gass them.
When i first put my CO2 on my tank i had all manner of issues and confusion about how to use it. Asking many questions helped me out.
If you have not already invest in some KH4 solutions for your drop checker... This will give a better colour reading for the target 30ppm CO2 then the chart which is in the books JBL supply. The KH/PH relationship can be inaccutate as other things in your tank can effect your PH, i think you mentioned something about your gravel raising your ph? if so don't use this as as be all and end all of what your CO2 levels are at...
more info here and other places...
http://www.aquascapingworld.com/magazine/July-2008/July08/Understanding-the-pH-KH-Relationship.html
The JBL kit i got and you probably have came with a spiral CO2 reactor, this is where u count the bubbles, but it does take a while for it to "run in" so you can read them properly, so adjust the small silver dial on the from of the value till you see bubbles coming up the ladder, for the first couple of days of use keep this turned down, so that just the occasional bubble comes through. After a while a film builds up on the path of the bubble up the reactor and the whole thing becomes more predictable. From the brief read of the mail on my phone email (which got deleted by accident) you mentioned bubbles coming through about half the size of a 5p, was that from the spout at the top or coming up the spiral? if it is the second one of those that is a direct result of the spiral not being run in yet.
In summary, adjust the CO2 on the dial on the front of the value, turn it down to almost off for the first day or so to run the reactor in so you can count the bubbles accurately or at least see even size bubbles going up the spiral. Get the KH4 solution for your drop checker (assuming you havnt already) and use that by turning the CO2 up slightly over a few days to hit the target level of CO2.
I've replaced my reactor (spiral thingy) with a ceramic diffuser now as i think it give better CO2 economy.
Couple of last points....
How planted is your tank?
Can we see some piccys?
Best regards,
John
p.s Hope i don't sound patronising at all, i only got a brief read of your message and it sounded like you were a touch lost. I'm happy to answer questions from my experience, and so are many more here with much more indepth knowledge then me. 8)
