Increasing CO2 ppm ideas...

[Sly_Fra]

Hi all,

Just got myself a Hagen CO2 reactor, and it is set-up at one bubble every 2 seconds. And I have a very fine diffuser for it.

My tap water is at 7.8 of pH approximatly. With this bubble rate of CO2, pH is down to 7.2 before lights are on, 7.4 when time to say goodbye (just tested 5 minutes ago). The CO2 reactor has been installed for 36 hours now (before this, random DIY bubbling rate and poor quality diffuser).

Here are my other pH influencing parameters:

Volume 33Gal
GH: 2.5 Degrees
KH: 2.8-3 Degrees
Temp: 78 Degrees
Fert: PPS Pro
Fish: Gouramis (Couple Dwarf, couple pearl), Otos (x3) and Rasboras (x10)

So with this KH and this pH, it gets my CO2 concentration to around 6ppm max. I am targetting for 15ppm to help my many many plants, and get Riccia to pearl...

Doubling the CO2 rate is very possible, but would double the yearly cost of CO2 (I'll do it if it is the only option though). Tanic acid (IAL for example) would lower pH, but I am not a big fan of the tea-colored water...

Will a few more days of this CO2 rate lower the pH some more? Again, it has only been less than 2 days of descent bubbling rate. If yes, then I'll wait. If no... any suggestions?

Thanks

 

[ChizerBunoi]

If your co2 bubble rate is constant during lights on for the past 36 hrs then it will not go down any more unless the new reactor is not as efficient either. How are you diffusing the co2 into your tank?

You could reduce the PH down to 6.8 which will give you 15ppm approximately at KH of 3. Or you could raise KH to 9 and keep the PH at 7.2. I'm just wondering why your KH is so low to begin with? Are you using spring/ro water?

Either way you should be fine.

 

[Sly_Fra]

I use the diffuser that was sold with the Hagen CO2 reactor kit.

Question is, how do I lower my pH to 6.8? My fish and plants will prefer acidic waters...

My water is tap, but I do have a filter and salt softener for all the water system of the house because of very old aquaduc conduits... (lots of iron in the water before this...)

 

[Faile]

While increasing the tanic acid would decrease the pH it would also lower the KH. The only way to change the pH without also affecting the KH is to increase the CO2 level. The only way to do this is to use a more efficient method of diffusion, increase the amount of CO2 being injected, and/or reduce the amount of CO2 being gassed off at the water surface (ie. get rid of air stones, ensure filter return isn't splashing, etc.).

 

[ChizerBunoi]

How many bubbles per second are you injecting at this moment? Do you have a lot of surface agitation? What filter are you using? Is it a HOB or canister?

 

[Sly_Fra]

I am using a Eheim external filter, with return water at surface level. Very little agitation. I have no airstone. I am at 30 bubbles per minutes (1 bubble every 2 seconds approx)

Thanks for the hint on tanic acid. I guess pH down chemicals aren't such a great ideas either huh...?

 

[Faile]

You definitely don't want to use pH down chemicals. Just like tanic acid, they won't increase the CO2 level and even worse they'll make you pH very unstable if you add enough to actually drop your pH. This generally leads to very poor and often deadly situation for fish.

I've got a feeling that you are using the kit on too large of an aquarium to have much effect. What you've purchased is basically DIY CO2 in a pretty package with a passive diffusion method. In most situations it's not going to provide enough CO2 for a 5 gallon aquarium, let alone the 20 gallon aquarium that they claim it will work on. What size is your aquarium?

 

[Sly_Fra]

OK thanks, I'll increase to 1bps and monitor the evolution. What I have it this thingy here: Fluval CO2 88 - Pressurized CO2 Kit - Pets & Ponds

 

[Faile]

Okay, so it's one of those mini pressurized setups. That will be much easier to deal with. Another step you can take to increase the CO2 levels, would be to put the diffuser under the intake of your filter. This will cause any undissolved bubbles to get sucked into the filter giving the CO2 more time to diffuse.

 

[Sly_Fra]

OK will try this. Will it do a misty tank tough? And noisy as the micro bubbles go into the propelor?

On a different subject, anyboby knows it teh air gun 88g cartridge will fit on this? If yes, much cheaper...

And a third subject while at it... Any advantages of stopping CO2 at night to save on the gaz???

 

[Faile]

The Eheim that you're using is a canister filter and not a HOB (hang on the back), correct? If so the bubbles should be completely dissolved before being returned to the aquarium. It's hard to predict whether or not it will result in any noise without giving it a try, unless someone else with the same model has tried it and can chime in.

There's really only one advantage to stopping the CO2 at night, and that is not having to refill the CO2 cylinder as often. Then again there really aren't any drawbacks either.

 

[Sly_Fra]

Filter is a HOB. Tried it, and no mist, no noise, no change (yet) in pH either though.

I guess the best way to stop it at night is with a solenoid valve? Any recommendations on these?

 

[ChizerBunoi]

That is correct. I use PH controllers with my setups but you can plug the solenoid inline and have that plugged into your power bar with the timer for the lights. You will want to make sure that you have the proper adapters to connect to the regulator or air line tubing (inline).

You can buy an adapter that will allow you to use larger paintball cylinders with this regulator.

 

[Sly_Fra]

OK, let me get this right.

I currently have the pressurized bottle and a needle valve (Hagen), then tubing all the way to the bubble counter, then from the bubble counter to the diffuser.

I put the solenoid between the needle valve and the bubble counter? Or does the Solenoid REPLACE the needle valve???

And that adapter you mentionned, where/how do I plug that???

 

[Sly_Fra]

Re-phrase: The Hagen kit comes with a a neddle valve + regulator:

Also, my pH is now at 7.2 but my KH is still at around 2.5d (I am now running 1 bps). Once I will have the Solenoid, I expect to increase to 2bps. But I woonder, should I try to increase KH with something like Seachem Alkaline Buffer...?

 

[ChizerBunoi]

An easier way is to just add some sodium bicarbonate (NaHCO3), aka baking soda. Add 1/2 tsp for each 100 litres to raise it 1 dH. 3 KH is the absolute minimum that you need for a planted tank.

Yes the Seachem alkaline buffer was designed for raising KH and maintaining the ph in a certain range.

 

[Sly_Fra]

Thanks ChizerBunoi,
The adapter for air gun you mentionned, it will work with this Hagen regulator?

 

[ChizerBunoi]

Yes and you don't have to buy it from that website. Just take your regulator into a paintball shop and they will have the proper adapter. Just make sure your new co2 cylinder can utilize the new adapter. Just note that you are still restricted to using a paintball cylinder, and a not a standard 5lbs cylinder (unless you get all the conversions for that tank as well).

 

[Sly_Fra]

The only cylinder I have right now is the disposable Hagen. I went to the only paintball shot in town today and they did not have this adapter. I'll get it from the web somewhere.

What do you mean "Just make sure your new cylinder can utilize the new adapter"? This adapter works with co2 cylinders, so this combo should work:

Hagen Regulator -- Adapter -- Paintball Rechargeable Cylinder ?

 

[ChizerBunoi]

The adapter in my original posting from rap4.com will work with regulator co2 cylinders. I'm surprised that the paintball shop did not have any adapters. Did you bring your regulator in?

From other peoples opinions on the plant forums, ada has an adapter that would work also. But you should call to confirm as ada disposable cartridges are 74g and not 88g. A standard 88g has the following thread M16 x 1.5.