Help with strange CO2 behavior
I have a 20g high tank with about 16/17 gallons of water, 65w Aqualight, Eco-complete, an Eheim 2213 and an Aquaclear 30 for filters, and 2 Hagen CO2 systems with a ladder on each side of the tank. Water parameters are:
pH = 6.8
ammonia = 0
nitrite = 0
nitrate = 10
phosphate = 1
KH = 5
gh = 6
CO2 = 24 ppm per Chuck's calculator
Water temp is usually 78, but has been going up to 80-82 due to temps over 100 here (I have lousy A/C). I have quite a few stem plants, mostly elodea and hygrophila polysperma.
When I got home from work today, I noticed that the tiny CO2 bubbles released from the top of the ladder are congregating at the water surface along the sides and front of the tank. I have a row of little bubbles just sitting there and some have moved out into the middle of the tank. Is this because the water temp is warmer? I have fish and shrimp in this tank and none of them seem to be in distress, but it looks really weird. I set the Aquaclear on low output during the day so it doesn't deplete the CO2 and turn it full open at night to add a little oxygen to the mix. I'm wondering if I should leave it full open during this weather.
None of my plants are pearling, by the way, which they did do the first week or so before the brown stuff grew into a nightmare. After a horror of a time with brown dust-bunny stuff that killed off nearly all my stem plants, I yanked them all out and threw away the ones that were "infected," soaked the others for a couple of days in tap water, cleaned my gravel good and replanted, adding about 20 stems of elodea. No algae except the slightest sprinkling on the CO2 ladders and a little on the glass and a few leaves. Plants are growing visibly each day and all little inhabitants are doing well.
Any info on this CO2 issue will be welcome.