I have a pressurized CO2 setup on my 50 G planted aquarium. During the day, the bubble count in my reactor has a constant flow that keeps the pH around 6.7. I know that during the night plants are supposed to give off CO2 lowering the pH overnight. In my aquarium the opposite happens. When I wake up in the morning there are far fewer bubbles than during the day and the pH is up around 6.8-6.9. The temperature in the room stays the same, and the water temperature drops maybe 1 degree overnight. I would like to keep the pH around 6.6 to keep over 30ppm of CO2 in the aquarium at all times. My fear is that one morning I might wake up and all of my fish will be dead because the CO2 actually dropped overnight like it is supposed to. Does anyone have any suggestions besides buying a probe, controller, solenoid?
CO2 question
- Thread starter broll
- Start date
No. Watch the fish. They will tell you everything you need to know. As one of my posts read, never trust test kits. Why? Allow me to explain:
My 75g "tested" (recent)
pH = 6.2
KH = 13
CO as derived by "the chart" = 264ppm
Fish deaths in the last 6 months = 2 (one to stress, one to jumping out of an open top tank)
Fish deaths in the last 3 months = 0
Always make CO2 changes in small increments. If the fish are ok in the morning, give the knob a small twist. Still fine at lights out? Leave it. Check the next day. Fish breathing heavily? Divide previous knob twist by 2 and check later in the day. Rinse, repeat, set!
My 75g "tested" (recent)
pH = 6.2
KH = 13
CO as derived by "the chart" = 264ppm
Fish deaths in the last 6 months = 2 (one to stress, one to jumping out of an open top tank)
Fish deaths in the last 3 months = 0
Always make CO2 changes in small increments. If the fish are ok in the morning, give the knob a small twist. Still fine at lights out? Leave it. Check the next day. Fish breathing heavily? Divide previous knob twist by 2 and check later in the day. Rinse, repeat, set!
If you have 45ppm, I would keep it there for a while and see how the plants do. I just checked my CO2 levels tonite and I have 45 ppm in both of my planted tanks. I am doing DIY CO2 via soda jugs and yeast solutions. I think 45ppm is plenty and would NOT shoot for 100ppm at all. Too much of a good thing can be BAD, and this holds true for CO2. If you do decide to go higher, keep a close eye on your fauna, lest they perish while you try to maximize your flora.
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I have seen many state that ~30ppm is the "optimal" level, and that anymore above that is excess that the plants cannot even utilize, but I've never seen any scientific proof to corroborate that. Of course, I haven't seen proof to corroborate a lot of things that I generally accept. Personally, I have seen some plants grow better at CO2 levels higher than 30ppm. However, I tend to try to push my plants to their growth limits anyway, and have done so to the detriment of my fish a few times. After seeing just how much CO2 I could get in my tanks, I ahve decided that levels around 45 are good enough for me, and with DIY it is a bit difficult to maintain levels higher than that for any extended amount of time. Maybe with Jell-O in my jugs I could do it, but why bother...
PS: I have one tank that I can push the pH level down to 6.2 and all the fish are fine (tetras, corydoras, SAE, CAE, yoyos, barbs, RTS, gouramis, khulis, mollies, etc...). However, in my tank with hillstream loaches, glass cats, amanos, zipper laoches, SAE, CAE, otos, etc...) any pH level below 6.6 and my Amanos, loaches, and glass cats head for the surface, probably due to the high CO2 level, not necessarily the low pH level. CO2 levels around 100ppm in that tank correspond to the 6.2 pH level.
I too am learning moderation...
I too am learning moderation...