[Fishedout]

I have a 6x2x2ft partially planted tank that is closer to heavily planted than lightly. I run one 5lt diy co2 bottle that is hooked straight into my filter pick-up with 1gal of water, 2 cups white sugar & 1/2tsp bakers yeast. My co2 levels vary between 14 & 20ppm. Without the co2 bottle hooked up the co2 level soon drops to just 3ppm. I have read numerous posts that claim diy co2 is no good on any tank over about 40gal. Am I just lucky or is there some other explanation as to why my co2 rig works so well?
I'm certainly not complaining. Just curious.

 

[redman88]

how close the to output of your filter is your device for mesuring your co2 lvls?

 

[kid creole]

I think many folks just find 14 -> 20 -> 3 is unacceptable. Consistent 30 to 40 is generally the goal. I think in a low to medium light situation any extra CO2 is just a bonus. From what I've read, the folks who have been successful in getting CO2 into the tank with DIY have 2 or 3 rotating DIY setups, and 5l is the largest I've heard of.

And if you say that you measure your CO2 by comparing KH and pH, get ready for the barrage telling you that's not correct because other things affect it.

 

[Darkblade48]

And if you say that you measure your CO2 by comparing KH and pH, get ready for the barrage telling you that's not correct because other things affect it.

+1. Are you using a drop checker with a 4 dkH reference solution? If so, where is it positioned, relative to your CO2 output?

 

[Fishedout]

Those PH - KH charts are totally meaningless IMO. No I don't use the drop checkers as they only give you a rough guide at best.
I use Vitakraft CO2 test kits. They measure in mg/lt using the 2 regents to get a color change. The color change is from clear so it is very obvious.
I use a syringe to remove some of the aquarium water into the test vial. I take the water from the opposite end as my pick up & spray bar which are in the same end of the tank together. These tests actually require agitation between the addition of each drop of regent so I imagine the test results are probably lower than the actual content, assuming they are even half accurate.

My co2 rig is rotating 5lt bottles. When one dies out I simply hook up the next one that I make the day before. These run straight into the canister filter pick up & I can count the bubbles as they pass through a clear section of the pick up hose that I installed for just that purpose but to be honest I don't pay much attention to the number of bubbles until I know it is starting to get close to when I expect the mix to start to die off.

My mix is 2 cups of plain white sugar with 1/2 teaspoon of Lowans bakers yeast. Each bottle lasts me for 3-4weeks. The old bottles then go onto my 30gal as they are still producing enough co2 for a smaller tank.

The tank has 8 x 40w T8 tubes mounted on a custom light stand & reflector. I'm not after more co2, if I wanted that I would spend the money on an injection system. I'm very happy with the way my plants grow in this tank. Will post pics when I get a new camera. (kids dropped & busted my old one). I'm just curious as to why my results with DIY co2 are so different to what other people seem to have experienced.

 

[essabee]

When I was using my 'Madhatter System DIY CO2' it was supplying gas to 3 densely planted tanks using 5 WPG lights, a 240G, a 145G, and a 30G. I was quite satisfied with the performance of the system and persisted with it for 2 years. I had 3 parallel 40L generators with one being charged weekly on Saturday by rote and the system stored the CO2 generated at night for use for the next day. I added more planted tanks and therefore decided to go pressurised instead of increasing the capacity of the system.

 

[Gatekeeper]

I find this highly suspect. I can't find any info on the test kit you are using.

But at the same time, if it ain't broke, don't fix it.

 

[plantbrain]

I used a DIY for 4 years on my 90 Gal with 2x 175 W MH's.

I used 2-3 bottles of , 2 liters each to do it.

Had to keep up, thought things did pretty good.

I had 30ppm however.

PITA to keep up with the CO2, the test kit method you have does NOT ensure it's accurate.

Any non carbonate buffer will throw the test off, 2-3 10 reagents, that does not matter.

Also, 8 bulbs x 40 Watt over a 6x 2 x2 ft tank that are DIY T8's?

This is only 1.7W/gal.

And this is a custom T8 reflector/hood, who knows how much light you might have, but it's certainly less than the T5's in the same wattage ranges and tank sizes and less intense than typical PC bulbs.

With low light, non CO2 is possible.

I think once you use the gas tanks, you'll see what you had been missing.
Having used DIY CO2 for a long time, I would never go back again.

Regards,
Tom Barr

 

[jmhart]

It's not so much that DIY on large tanks "can't be done", it's more that it's a tremendous headache to achieve good levels of co2 and keep those stable. Also, over the course of a year, the sugar costs really start to add up, making a pressurized system that much more desirable.

 

[Fishedout]

Also, 8 bulbs x 40 Watt over a 6x 2 x2 ft tank that are DIY T8's?

This is only 1.7W/gal.

And this is a custom T8 reflector/hood, who knows how much light you might have, but it's certainly less than the T5's in the same wattage ranges and tank sizes and less intense than typical PC bulbs.

With low light, non CO2 is possible.

I think once you use the gas tanks, you'll see what you had been missing.
Having used DIY CO2 for a long time, I would never go back again.

Regards,
Tom Barr

What's this DIY T8 bit you mention. I don't think I'm following what you mean there. I never mentioned diy T8's. Are you refering to the lights, then tank size then diy co2?

The reflector/hood is diy. That is basically just a wooden box painted flat white inside & I garantee that it reflects heaps more light than any polished reflector except for mylar film. Atually it reflects exactly 75% of the light. All the light is directed straight down into the tank. There is nowhere for the light to go but down into the bottom of the tank. I wouldn't argue that I would get more light from the T5's & PC bulbs you mention as that is absolutley correct. I already had these fixtures though so that is what I used.

I have an injection system on a 4x2x2ft so I do know what I am missing. I'm just not worried about it as I still have excellent growth in the 6ft with diy co2. Most of the plants are fairly low light, java moss & fern, crypto wendetti, a few anubius & one large sword that despite the higher light requirement grows faster than the rest do.

I don't know why it all works so well. That's why I posted what I'm doing & the results I'm getting. I'm trying to figure out why it works so well. I've racked my brains & can't work it out. I'm certainly not complaining though.

 

[kid creole]

I think this thread is going to get good soon. JMHO.

 

[trackhazard]

I think the point you are missing is that you have a low light setup. I have 2x54w T5 on a good reflector hung 10" over a 19" high tank tank and I can almost guarantee you I have better PAR at the substrate than you do.

Low light setup is nice because growth is slow and algae is easy. Unhook your DIY CO2 and I'll bet your plant growth will be relatively unchanged. At that point, I'd rather not even mess with the DIY stuff.

Charlie

 

[Fishedout]

I think the point you are missing is that you have a low light setup. I have 2x54w T5 on a good reflector hung 10" over a 19" high tank tank and I can almost guarantee you I have better PAR at the substrate than you do.

Low light setup is nice because growth is slow and algae is easy. Unhook your DIY CO2 and I'll bet your plant growth will be relatively unchanged. At that point, I'd rather not even mess with the DIY stuff.

Charlie

I'm sorry you feel that way trackhazard but I think it is you who is actually missing the point. I am well aware that I am running a low light set up & that the benefits of the co2 are being limited by the amount of light that I am using. If it makes you feel any better, I have plans to run 2 x 400w MH's over the top of it when I can afford an injected co2 system on this tank as well. I already have the lights but see no point in using that amount of light when I don't have enough co2 to take advantage of them. The original question that I am trying to get sorted out is why I get such high co2 levels out of a diy co2 bottle on such a large tank? As that is not the way it usually works. I have presented the details of my set up so that people know what I am doing & maybe people with more experience than myself can present me with theories of why it works as well as it does. If you must know the co2 is there primarily to lower the PH of this tank for the benefit of the fish without me having to resort to uppers & downers or peat in my filtration system as these methods are simply not a good idea IMO. The peat is ok to do but simply very expensive stuff to buy over here & it would cost me about $30aus every week to use peat in my filtration system from my understanding of how often it needs to be replaced.
I bet more people would have alot to say to me if I left my geophaguses & rainbows in my tap water with it's PH of 8.2.

As for you have higher w per g over your tank, well, that's very nice for you but is totally irrelevant to my question. I'm not asking about lights. Which is why I never mentioned them in my original post. I'm asking about co2 levels. Which is why I say that you are the one who has missed the point.

 

[Gatekeeper]

Getting awefully testy in here.

Fishedout, I believe Tom answered your question.

I used a DIY for 4 years on my 90 Gal with 2x 175 W MH's.

I used 2-3 bottles of , 2 liters each to do it.

Had to keep up, thought things did pretty good.

I had 30ppm however.

PITA to keep up with the CO2, the test kit method you have does NOT ensure it's accurate.

Any non carbonate buffer will throw the test off, 2-3 10 reagents, that does not matter.

I say we move along from this thread or direct the tone to a more positive light.