CO2 PPM Question

[dantra]

Originally Posted by jjp2

A drop checker is a tool which will get you in the ball park. Its color to ppm is determined by the kh of the liquid you use, 4kh turns green at 30 ppm. Its limitations are that it does not change color quickly, is fixed in one location, we inteprete the color so it is not accurate (green doesn't guarantee a CO2 ppm of 30).

Once you get the drop checker to green, you need to watch your fish as you continue to adjust up. They will display the signs of too much CO2. Some are more sensitive than others.

Exactly and I can only speak from my experience but once it turns green you should slowly and I do mean slowly turn it up just a touch and watch the fish. Be patient and turn it up once a day if needed. Again be patient and once you reached the point where the fish becomes lethargic then back up just a bit.

Originally Posted by NJAquaBarren

A lot depends on how much growth you want. I read that 15ppm was plenty for healthy vigorous plants, so I haven't stressed about reaching 30ppm. Currently I'm at ~15ppm in my 84G tank and everything I've planted is healthy. Some of the new stems are growing slowly so I may bump it up for a while. Once the scape is where I want it though, I'm thinking back to 15ppm to reduce maint.

Actually cutting back on the CO2 is the worst thing you can do to control plant growth. What one should be concentrating on is excellent or close to it CO2 saturation into the aquarium, then if you don't limit ferts and limit light, you'll be fine.

Light and only light should be the only catalyst used to control plant growth. Anything else is just asking for trouble. Cutting back on CO2 to control plant growth will most certainly induce algae.

[Guns286]

Has anyone used the SMS122 PH/CO2 Controller? I saw it on E-bay for a good price but, is it worth it? It seems to take the guess work out of balancing PH and CO2.
And NJAquaBarren, I am planning on following the PPS-Pro dosing plane and it calls for 15ppm CO2. That seems to work for you?

[Hoppy]

The problem with the PPS Pro dosing plan and its call for 15 ppm of CO2 is that the measurement method used to determine that you have 15 ppm isn't accurate enough to tell you that you have 15 ppm. More than likely the 15 ppm the author of that plan thinks he has is much closer to 5 ppm. If you really want to have 15 ppm, you need to invest lots of money in a specialty CO2 measuring probe that can accurately tell you just how much CO2 you have at any location in the tank, and it does vary widely around the tank. Wouldn't it be better to just increase the bubble rate, slowly, of course, until you get pearling of the plants within a couple of hours after the lights come on? That might end up being 15 ppm.

[Guns286]

Good point Hoppy. Like I said, I'm still VERY new to this and am looking to as many "tricks of the trade" I can get. Thanks.

[NJAquaBarren]

Left C posted a long and detailed post on CO2 recently..at least I read it recently. In it was a color chart for drop checker fluid. Search the web, I've seen them before.

[Darkblade48]

Originally Posted by NJAquaBarren

Left C posted a long and detailed post on CO2 recently..at least I read it recently. In it was a color chart for drop checker fluid. Search the web, I've seen them before.

You must be talking about the Ph colour chart for bromothymol blue (part of the API pH test kit).

[Guns286]

I'll take a look for the color chart but if Sumo sells different PPM solutions, do I need to now? If I want 15ppm I just have to get the right solution. I'm not sure how accurate it is, but I guess its worth a try.
What about the SMS122 PH/CO2 controller? Does anyone recommend it? Or, would it just be a waste of money?

[Darkblade48]

Originally Posted by Guns286

I'll take a look for the color chart but if Sumo sells different PPM solutions, do I need to now? If I want 15ppm I just have to get the right solution. I'm not sure how accurate it is, but I guess its worth a try.

It is up to you, but most people (now) agree that 30 ppm of CO2 is the ideal level. This is why most people use a 4 dkH reference solution and not a 3 or a 5 dkH reference solution.

Originally Posted by Guns286

What about the SMS122 PH/CO2 controller? Does anyone recommend it? Or, would it just be a waste of money?

I would save your money for other things. I do not believe a pH meter is required in a planted tank.

[hbosman]

Originally Posted by Darkblade48

It is up to you, but most people (now) agree that 30 ppm of CO2 is the ideal level. This is why most people use a 4 dkH reference solution and not a 3 or a 5 dkH reference solution.


I would save your money for other things. I do not believe a pH meter is required in a planted tank.

I would agree. A ph meter is still measuring ph in the aquarium so, it is susceptible to differences by buffering caused by phosphates and variable kh in the tap water.