One of the canisters seem to be sucking a little air... I can see the tiny bubbles rushing through the intake tube... yet that doesn't seem to affectanything...water change still in progress...
After the tank has been refilled, the canister that had been sucking air was giving off micro-bubbles... to get rid of those I had to switch it off, open it, fill it with tank water and switch it back on again... now it's working fine but the tank is cloudy again... so much for the experiment.
Next week I'm back to switching off the canisters before the water change... I'd still get a cloudy tank afterwards but it'll be less tiresome!
Yeah, I should try that... must check whether I have some silicon left... or else I'll have to ask Jeff from the LFS - he always has silicon for the tanks he builds...
By the way, I went to see him yesterday and he was building that massive glass tank for his store... 10 feet by 2 feet by 32 inches tall... that made me drool so much... I wish I had the space for such a tank...