Started On Diy Co2...questions

[trojannemo]

well i finally finished my DIY CO2 system.
i used 2x 2-liter soda bottles, silicone tubing going straight through the bottle caps (sealed and cured with silicone sealant). the tubes go through individual check valves and then to a t-connector that connects to the main line going into the tank...which ends on a glass air stone.

i have some questions for ya:
1- i understand the addition of CO2 will lower my pH - i have moderately hard water with a pH of 7.5, how long can i expect the CO2 to drop my pH? will this drop be sudden (as to harm the fish) or occur slowly?

2- is it a better idea to change both bottles every 2 weeks, or change 1 bottle every week, alternating the bottles?

3- how long before i'm supposed to notice a difference in my plants? not really worried about getting crazy growth, but rather checking that it is working!

thanks!

 

[Mr Bliss]

well i finally finished my DIY CO2 system.
i used 2x 2-liter soda bottles, silicone tubing going straight through the bottle caps (sealed and cured with silicone sealant). the tubes go through individual check valves and then to a t-connector that connects to the main line going into the tank...which ends on a glass air stone.

i have some questions for ya:
1- i understand the addition of CO2 will lower my pH - i have moderately hard water with a pH of 7.5, how long can i expect the CO2 to drop my pH? will this drop be sudden (as to harm the fish) or occur slowly?

2- is it a better idea to change both bottles every 2 weeks, or change 1 bottle every week, alternating the bottles?

3- how long before i'm supposed to notice a difference in my plants? not really worried about getting crazy growth, but rather checking that it is working!

thanks!

The pH will drop by ~0.8 and it won't shock the fish. If the pH won't drop, it'd be a sign that you have an inefficient diffuser or too much surface turbulence/aereation.

It's better to alternate the bottles to keep the CO2 stable, as stability is more important than achieving a high ppm. You may see pearling within 24 hours (depending on lights and nutrients), and the growth should improve noticeably within a week.

 

[trojannemo]

well i have T5-HO lighting that i've been told was "so good" i needed some CO2. i've also got the nutrients going, feeding 7 different liquids on a schedule + using eco-complete substrate

pearling huh? never thought i could see that with a DIY kit

 

[aaronnorth]

pearling is achieved when there is anough Carbon available to plants, so if you want it, then add more, but be careful not to gas your fish, and higher leevels of CO2 with a DIY kit ismore prone to algae attacks (because of fluctuation) as it is hard for the mixture to keep outputting the levels required.

WHat are the 7 liquids? seems like a lot that you may not particularly need.

 

[trojannemo]

WHat are the 7 liquids? seems like a lot that you may not particularly need.

i think you and i already went over this!
im using flourish, flourish excel, flourish iron, flourish trace, flourish potassium, flourish phosphorus and flourish nitrogen. im using a modified version of seachem's recommended dosing schedule dosing 6 days a week with a 10% water change on the 7th day.

 

[aaronnorth]

i think you and i already went over this!

yes we did....well you know my verdict

 

[trojannemo]

soooooo it would appear the first attempt at the mixture was a failure. i think we just cooked the hell out of the yeast when my girl decided to mix it in HOT water rather than warm
this time i tried out a (i think) better mixture following more detailed instructions and at least it looks better. also removed all the excess tubing and now made it be taut by holding it in place with a suction cup, so the gas has nowhere to go but up

according to this guy's instructions by tomorrow morning i ought to start seeing bubbles coming out of the airstone (i.e. it should be visible that its working)

wish me luck

 

[trojannemo]

well i have bubbles alright...a constant stream of very fine bubbles coming out of the air stone. everywhere i've read it's mentioned that you should expect a certain amount of bubbles per minute or every so many seconds. this looks more like if a very weak air pump was plugged into the air stone as there is no delay between bubbles...just a constant stream
is this good or bad? it's been going on for about 3 hours now and the fish aren't freaking out. by midnight tonight (~ 6 hours after it started) i'll test the pH. am i getting too much CO2 production or is air getting into the mix somehow? i'm confused

 

[SuperColey1]

airstones are no good for CO2 diffusion. You want a limewood stone or a cheap ladder. I used to use a Rhinox glass/ceramic diffusor when I used to have DIY and it worked fine. If you choose this route then ignore the sellers tank size guide and buy the model lower down, they are always a bit hopeful with their suggested capabilities just like filter manufacturers are.

Ph will be in the region of 0.8 as suggested above. 1Ph should be the max unless you have off the scale low or high KH.

The drop will depend on the efficiency of diffusion. Namely if you reach 30ppm (which I doubt with DIY) then it will drop by approx 1ph. If you can keep the ppm consistent then it will remain at 1ph less than your tap water (after tap water has been sitting for 24 hours.)

The drop is as sudden as your efficiency allows. If I were to inject my CO2 at 20bps then the CO2 saturation would be deadly to fish but it would drop the Ph quite quickly. DIY has no chance at all (no exaggeration) of doing this. You can't even control the amount you are injecting as it is dependent on the effectiveness of the mix which even when thebest mix there is will start slow, then peak then drop off etc. hence the suggestion that 2 changed alternatively makes the injection more consistent. This way while one is dropping off, starting up the other is peaking etc.

Change them both weekly not fortnightly. 1 on weds, one on Sat (or other days you choose.) People warble on about how long the mix will last and are missing the point. You don't want one gradually reducing its output. You want it to be producing well and not tailing off.

When you have finished the Seachem Trace don't buy anymore. Just up the daily dosing of Flourish by 5% and it will supply what the trace was without having to buy the extra bottle.

The bubble count (bpm/bps) that you refer to is not what you see coming out of the diffusor (airstone in your case) it is the rate at which bubbles pass through a bubble counter. The better the diffusor the smaller it produces the bubbles therefore 1 bps through the bubble counter may produce 1 million microbubbles (exaggeration) when passed through a top diffusor. Similarly the same 1bps passed through a ladder diffusor will produce........1bps on the ladder. It will get smaller as it remains in contact with the water.

The reason for trying to get the initial bubbles that enter the tank water as small as possible is so that as much of the 1bps as possible is in contact with the water for as long as possible. Large bubbles are much more bouyant than a 'million' microbubbles, therefore in a tank with no current the large bubble will break the water bubble speed record on it's way to the surface whereas the 'million' microbubbles will take much longer. In a tank with good current the microbubbles are much more likely to be carried around the tank by the current whereas the large bubble will still thunder its way to 'Gas Heaven'.

My guess is your airstone is producing bubbles which are shooting straight to the surface and therefore you won't be getting very efficient diffusion at all.

AC

 

[trojannemo]

thanks for your many suggestions!

after 13 hours of constant streaming of CO2 bubbles, i tested my pH and if it's dropped at all, it's done so by 0.1-0.2 pH only. i can't tel for sure because the API liquid test has a 7.2 reading and a 7.6 reading. my pH has always hovered around 7.5 but i can't really be sure if it's down to 7.4 or 7.3 like i think it is.

you are right in saying the bubbles are shooting straight up. they just go to the surface. it so happens that when i placed the airstone (without thinking much about it) i placed it directly under one of my filters, and the bubbles coming out of it are collecting right under where the filtered water comes out so, so there's a massive collection of tiny bubbles there. kinda like a betta's nest

i got your message regarding the diffusion loud and clear - question is, where do i get ahold of one of these ladders or a glass diffuser? i searched around for the best materials i could find but stores down here dont seem to be too much into CO2 injection the closest i came to a glass diffuser was this stone i'm using now, which is not made out of the normal rocky substance air stones are made from but rather from a glass material that the store owner recommended highly for CO2.

 

[SuperColey1]

http/cgi.ebay.co.uk/Lot-of-2-Brand-New-C...1QQcmdZViewItem

 

[trojannemo]

thanks. seeing what that one looks like, i think i like the design of this model more:

ebay link

dont you think that design is better, considering what's been said so far? looks nifty too

 

[SuperColey1]

Personal preference of each user on these. I prefer the more minimal ones and not a great fan of the spiral. Not so sure it is needed as well as the ceramic disc.

The link I gave is also for 2 units which means you can just swap over weekly while the other cleans.

AC

 

[trojannemo]

Personal preference of each user on these. I prefer the more minimal ones and not a great fan of the spiral. Not so sure it is needed as well as the ceramic disc.

The link I gave is also for 2 units which means you can just swap over weekly while the other cleans.

AC

thanks. cant argue with your logic. back to the less expensive ones then.

btw, i can now confirm my CO2 is working. The bubbles have not stopped since yesterday when they started, now being about 29 hours straight. the fish are all fine.
my melon sword, the biggest of all my plants at the moment, has a steady stream of bubbles coming from it's center stalk(?), as well as having doubled the size of a new shoot
from yesterday to today

can't wait till i get the glass diffuser going as well. thanks for all the help guys