Do I Need C02?

[Fluval-1200]

Have just bought myself a new tank and swapped all my gear from my other tank to this one.
Before I had a 75gal with 4 t5 39watt bulbs and was 24'' deep.
This new tank is 80gal and has 2 t5ho 54watt bulbs and is 20'' deep.
Im running a pressurised c02 system and have got my drop checker to a green - lime green colour.
I only have a couple crypts, vallis, cambomba and amazon swords In the tank atm as most of my plants were destroyed while using a temp tank (pleco)
 
Do I actually need c02 as im not running as high wpg as before, im having quite big ph swings and my kh is 3degrees and gh is 6degrees.
Im thinking due to not having as powerful lights my co2 isn't being used up enough and is causing these ph swings, I don't want to play with my water chemistry at all in terms of gh and kh.
 
 
 

 

[levahe]

Its normal for the pH to drop when using pressurised co2, and is nothing to worry about because it won't harm anything in your tank.
How much is your ph changing?

Co2 in a planted tank is entirely optional, if you dont want it you can go low tech but you may have to have dimmer lights in order to avoid algae. The only way to find out is to try it to be honest. As long as you dose micros and the lights not too bright it will be ok.

 

[Fluval-1200]

it goes from around 7.6 to about 7 most days, but I have seen it go as low as 6 which is quite a drastic drop. Will it even out abit once I add more plants?

 

[fm1978]

I get how important CO2 is for plants but if it's making your pH drop by that much, I'd be put off a bit. A drop from 7 to 6 is a lot...pH of 6 is 10 times more acidic than pH 7. I'd either get rid of it entirely, or reduce it a bit to bring down those pH swings!

 

[levahe]

A drop of 1 pH won't harm any livestock or plants, or anything for that matter. Its supposed to go down when injecting co2. It happens to every single aquarium that injects co2.

When the co2 turns on the pH will go down gradually untill the co2 turns off, and then it will go back up gradually,

 

[Fluval-1200]

It went from 7.4 to 6 today, 6 was just before the co2 going off.
I might turnt the co2 down a tad as a 1.4 ph drop is quite a lot.

 

[levahe]

From what I remember you said on another thread your kh is 3, a low kh means there is less resistance to pH change. If you had a high kh of say 12 or 15 it would be more difficult to move the pH, so it would only drop by about 0.8 or so.
How are your fish acting? If they aren't hanging about at the surface or looking like they are gasping then your co2 level may be ok

 

[Fluval-1200]

From what I remember you said on another thread your kh is 3, a low kh means there is less resistance to pH change. If you had a high kh of say 12 or 15 it would be more difficult to move the pH, so it would only drop by about 0.8 or so.
How are your fish acting? If they aren't hanging about at the surface or looking like they are gasping then your co2 level may be ok

This thread lol, I don't really want to play with the water chemistry.
 
Fish are acting fine, but I did lose a kribensis the other day.