Tetraplant Co2 Optimat

[targa66]

hi - I just bought a TetraPlant CO2 optimat to try to help with weak, non-thriving plants - need some advice:

The instructions say: "When using the carbon dioxide diffusion set you should avoid any form of ventilation during the illumination phase. This also applies to all additional devices on the rotary pumps."

- huh?? are they suggesting turn off the filter and airstone when the light's on???

Instructions continue: "The CO2 fertilisation should be released at night - i.e. without light - since plants can only absorb CO2 in connection with light."

- again - doesn't make sense - if plants can only absorb CO2 with light, why fertilise at night? or is that b/c of the time delay between filling the cannister and the actual release of CO2?

Then it says- "It is recommended to ventilate during a period of darkness."

What do they mean by ventilate? aerate?? does that mean I need additional oxygen during dark periods?

Finally, how often should I fill the cannister? I didn't get a CO2 test kit b/c the LFS who sold me the diffuser said there would be no problem for the fish to add the CO2. Is that incorrect?

Thanks for any advice.


My tank is 156 litres, fully cycled for about a year now, water is on the hard side. It's a bit understocked with various tetras, platys, swordtails and guppies. There's about 1-1/2 inch of pea gravel on the bottom. I've had some success with Amazon sword and anacharis but cabomba and vallis always waste away and die. Hornwort grows but doesn't root and ends up floating around.

 

[sjdriscoll]

These kits are not very good, especially for anything over 50 litres.

What they are trying to say is 'empty the tube of any CO2 at night so that there is none left to diffuse into the tank'. But don't worry, the tiny amount of CO2 that this kit introduces will not affect the fish (or the plants sadly).

Also any water turbulence at the surface will 'drive off' CO2, hence most of us only run airstones etc at night. Lots of people run lilly pipes to reduce surface agitation as well.

I ran one for 2 weeks on my 100 litre with no improvement in CO2 levels at all!

For a tank your size you could try (3 x) 2 litre DIY yeast kits all hooked up together or, better still, some pressurised CO2.

 

[targa66]

Thanks for your help... I wish I had asked before parting with £15! I'll set it up anyway and see if it makes a difference. I've just bought some new twisty vallis and another few plants - just wish they would survive.

When you say I could use pressurized CO2, isn't that what's in the cannister that fills the tube in the water?

thanks!

 

[sjdriscoll]

When you say I could use pressurized CO2, isn't that what's in the cannister that fills the tube in the water?

thanks!

Yes it is under pressure in the can but you cannot inject it continually, you have to squirt a bit into the diffuser tube and then wait for that to diffuse into the water. With a pressurised system you can set it to the flow that you require to achieve 30ppm of CO2.

You could look at running some DIY kits for a few quid if you don't want to go down the pressurised system route (£100 ish).

 

[targa66]

Yes it is under pressure in the can but you cannot inject it continually, you have to squirt a bit into the diffuser tube and then wait for that to diffuse into the water. With a pressurised system you can set it to the flow that you require to achieve 30ppm of CO2.

You could look at running some DIY kits for a few quid if you don't want to go down the pressurised system route (£100 ish).
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Thanks again - I've been reading up on the pressurized systems - a bit intimidating, so I'll look into the Nutrifin type kits.