PH Controler

[pkoenix]

I have a 180 gal Planted Fresh Water aquarium with a sump tank, UV , CO2, & PH controller set for 7.0. I have been turning off the CO2 when the lights are off and the PH jumps to 7.6, should I keep the CO2 & PH controller on 24/7?

[Fresh2o]

Ideally it should be on all the time. The controller will dictate when the CO2 will come on. You could try setting the ph limit a bit higher (7.2-7.4); the CO2 will still come on, however, it should be less than if set at 7.0.


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[Delapool]

Originally Posted by pkoenix

I have a 180 gal Planted Fresh Water aquarium with a sump tank, UV , CO2, & PH controller set for 7.0. I have been turning off the CO2 when the lights are off and the PH jumps to 7.6, should I keep the CO2 & PH controller on 24/7?

Here the CO2 is a bit expensive. I run the CO2 to come on about 1 to 2 hours before lights and turns off about 15 minutes before lights do.

My canister filters turn off (somewhat) when lights come on so as not to increase CO2 off-gassing. This is because my tunze co2 reactor runs at maximum to get co2 into the water when it is on. I still have an internal powerhead / filter running almost all day to push water around plants.

Tank ph will start at say 7.2 or so and drop to say ph 6.5 or so (and then come back up as CO2 off-gasses).

Must go and look at the reaction again.

[Delapool]

Found one:

http://ion.chem.usu.edu/~sbialkow/Cl...ic%20Acid.html

I had an idea that the addition of CO2 plus H2O gives carbonic acid and then further along decreases ph. And all without consuming carbonate buffers. So after CO2 injection stops, the ph will lift back up and kh is largely the same.

Must test this but my kh is largely stable (although soft tap water).

And as kh is not decreased, the normal rules of not changing ph suddenly don't apply so much. Not sure if I have that right?

[coralbandit]

It is normal for your pH to change when the co2 is on or off.
Many run their co2 with the light cycle only with the solenoid on a timer.
They also look for aprox. a 1 pt drop when the co2 is on compared to when the tank is outgassed and balanced with the atmosphere.
My 180 goes to 7.6 when co2 is off and I drive it to 6.6 with my milwaulkee controller.
I burn plenty of co2 also having a sump ,so I run 2 reactors on separate powerheads in the sump.
Hope this helps.

[pkoenix]

I run one reactor.Off it can go up to 7.6. My tap water is 7.6 very hard water Milwaulkee controller set at 7.0, I think that it is to hard on the fish I am going to leave it on 24 for now

[Delapool]

Do you have a kh test kit at all? You could test and see.

I'm hoping to test this week out interest on kh at start and end of co2 injection.

[pkoenix]

yes I have one. will test

[Delapool]

Bit incomplete on the testing, I really need a weekend to do this.

The CO2 comes on at 3pm. Not home then. Previous readings of kh=6 in January and kh=5.5 in April.

At 7.30pm:
ph probe - 6.8.
ph pen - 6.8 to 6.9
kh - 4
gh - 8

At 9.00pm:
ph probe - 6.7 (really need that second diffuser going!).
ph pen - 6.9 (filters are back on so possible)
kh - 5
gh - (didn't test)

Tap water ph was 8 (April was 7.7 to 7.8).

So I can't really say much so far except that kh probably doesn't drastically change.

[Delapool]

Tested tap water and got a kh of 5 (should of thought of doing that last night ).