Help with aquarium co2

[Daveb82]

I have a 55 gallon that I decided to finally add co2 to since my plants were doing semi ok (defently not great). I am trying to get my regulator set for the right amount of co2. My water out of tap is 8ph. I have had the co2 running for two days now

co2 turns on at 7:00am lights turn on at 8:00am
cot turns off at 6:00pm lights turn off at 7:00pm
I have no surface water disturbance.

I have a drop chcker (fluval) that I'm not sure if I installed it right. It was blue then went green and now it looks like just the top is yellow.

I did a ph and kh test just now and
ph is 7.8
kh is 130 which shows very low co2 right?
3.5ppm by my calculations or am I doing that completly wrong?

I have 1.5 bps right now. Should I leave it, lower it, or raise it?
Is it still too early after two days to tell?

Sorry for all the questions I am totally new to co2. And this forum helped me out HUGE on fertilizers so thought I ask about co2.

Thanks

 

[Sparky74]

Your drop checker says it's much higher than 3.5ppm.....

I personally don't trust the chart. Once my drop checker turns greenish/yellow, I call it good.

 

[mfdrookie516]

The chart is very accurate... under ideal conditions. But, it seems that it breaks down with higher or lower pH naturally... or if you're buffering the water. The drop checker, while sometimes slow to change, is a good method... it uses the 4dkh solution which is a known solution, and the co2 level drops the pH. Yellow isn't necessarily bad. If it's bright yellow, you'll want to lower it a bit. A yellowish lime green is where I always kept mine.

 

[Daveb82]

Bit of an update, and still a little help needed. I found out I had a faulty regulator with an attached solenoid attached which only shut off about 75% and still let 25% through. Got a new one and have it working better. Still trying to figure out co2 though. I just checked ph after running co2 for 6.5 hours (will turn off in 1.5 hours) and ph is down to 7.5 and kh is 140 which according to co2 chart has co2 of 7.5 ppm, nowhere near 30. My drop checker turns dark blue over night and by the time co2 shuts off is dark green. I know it says green is good but is only 7.5 ppm good? It has not turned yellow again since new regulator was put on. Should it be dark green or more a lime green? In a 55 gallon I am doing 80 bpm. Any help is appreciated. Thank you

 

[mfdrookie516]

I'd crank it up a little then... Are you turning your co2 on before the lights? You've got to turn it on 30 minutes to an hour before the lights to let the co2 build up... that way you can keep a constant level throughout the day.

 

[ldaniel]

Is your Kh reading degrees or a total bicarbonate number? A dKh of 140 is outrageous. If it is a total bicarbonate reading then divide by 50 to get meq/L then multiply by 2.8 to get dKh.

 

[Daveb82]

Test kit does it in ppm so kh is 140 ppm is that normal?

 

[ldaniel]

140ppm will = a dKh of 7.84. Yeah that is a fine reading.

 

[Daveb82]

So would you say I should crank up co2 and try to get it from dark green to lime green? Or leave it with a low co2

 

[mfdrookie516]

I would get it to lime green. I've had the best luck with lime vs dark. You may need to increase the time it's on before the lights come on as well.

 

[Daveb82]

So I turned co2 up and it's now a limish green but according to the charts I still only have 11 co2 ppm. My ph is still staying around 7.4-7.5 is the chart accurate at that high a ph? It's still that high after co2 has been on for 8 hours. Tap ph is 7.8-8 should I go by chart and add more co2 or go by drop checker and leave it?

 

[mfdrookie516]

As long as you're using 4dkh solution in the drop checker, go by it. While it's not the most accurate thing in the world, it can be more dependable than the reference chart. You could change out your solution to be sure.

 

[Daveb82]

I have the fluval co2 indicator with their liquid you add. I can not find anywhere if it is a 4dkh but I imagine it would be? Would that be accurate enough to go by since it's lime green

 

[Sparky74]

I see it this way...If you do it by the chart, you must have precise test results to compare on the chart to get an accurate result. If you are off just a little on both tests(KH and PH), it throws the chart out the window as a reliable source IMO.

I'm not dismissing the chart, but it adds more chance for human error.

I suppose you can mess up drop checker as well, but I find it to be less error prone.