DIY CO2 sytem

[guppygirl]

Ok, since my Foster and Smith order just came in with my 2 co2 diffusers, I just wanted to do a double-check on the 'plan' !
So if you see anything that you think could be changed, PLEASE reply, I don't want to make a mistake!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Container for yeast mixture: 1 gallon container
Yeast mixture: 4 cups of cane sugar
1/2 teaspoon of active dry yeast
1/2 cup of lukewarm water to mix the yeast in
1 Bulkhead fitting that will be drilled into the cap
1 check valve
1 splitter valve that's has adjustable flow,
2 Co2 diffusers from the Hagen natural plant system

Do I need to silicone the bulkhead fitting too?
Thanks!
Robin

 

[smithrc]

you'll need a lot more water than that... - hold on I'll just check our recipie...


We mix up in 500ml multiples.

for our 500ml containers we use this x1 and for our 2L bottles we use this x3 (or 4 if there is room)

90g of sugar,
1/2 teaspoon of bakers yeast
500ml of water

It lasts about 3 weeks.

 

[BobTheDog]

smithrc is correct... you need more water. The 1/2 cup is to initially mix the yeast with to "proof" it(make sure it is good). You put the yeast in the water with a small amount of sugar (I usually use same amount of sugar as yeast). In 10-15 minutes, you should have a brown foam on top of the water. This means the yeast is still viable and you can then mix it in with the remaining sugar and the additional water.

Also, I would silicone the bulkhead just to make sure you have no leaks. My biggest issue when I set mine up a few weeks ago was stopping all the leaks.

Good luck!

 

[guppygirl]

Ya whoops I forgot water.. ) Thanks guys!

 

[smithrc]

touch wood - i've not had any leaks... and mine is bodged

i peirced a hole through a 'soda' bottle top with a hot skewer, then put a bit of air line into it. itto that i jammed a plastic connector (again ait line ones) voila - bodges but working

I'm just about to go for a propper preasurised CO2 system though as changing the bottles is anoying.

when it starts to slow down the PH may start to change.
So if you can, run 2 smaller bottles at the same time - when one starts to slow - change it so the other will still be providing some CO2. if you stagger the changes, there will alwas be CO2 being added so the PH swings will be a lot less

 

[guppygirl]

So, can I just use the 3.78 liter bottle or should I get 2 2Liter bottles? I still have to do some other things before I start the co2, like put more gravel in, check water qualities, etc.
Oh and that brings up another question. My water properties are:
ph: 6.5
Ammo: 0
GH: 6 dGH
KH: 1 dKH

Most of these seem ok, but with the low KH, is it really ok to add co2? If so, how much co2 should I add? I looked at the table here, so It says I should add 11-12 ppm of co2. Is this ok?
Thanks,
Robin

 

[smithrc]

the table works diferently to that.

for good plant growth - 30ppm is a good target for CO2 levels
(** PLEASE CORRECT ME IF I'M WRONG HERE! **)

so you will need to measure your PH and hardness (KH)

your PH will change as the CO2 is added, the amount it will change depend on your KH.

so with your KH at 6 you will want to control your CO2 so that your PH is around 6.8. this will mean you'll have around 28ppm of CO2 in the water

 

[smithrc]

Woah... just re-read youe specs... A KH of 1º - thats really low.

I think ours is 14!

hmm... i may be muddled... one sec.

 

[guppygirl]

Hmmm... I'm sorta confused here...
my KH is 1, but my GH is 6. I saw from the chart that anything over 25 is harmful to fish?? Or is that wrong?
Edit: lol you posted first... yeah, it is 1. Do I need to raise it? How would I without raising ph or GH? Is that possible?

 

[smithrc]

right - in our planted 190,

KH is 8º
GH is 10º

PH is usually about 7.2

so with a KH of 8, PH 7.2 means that there is only 12ppm of CO2.

so now i'm working on a DIY way of keeping the PH at 7.0 using a PH meter and a valve.

 

[smithrc]

Do I need to raise it? How would I without raising ph or GH? Is that possible?

right... i'm not sure where GH comes into it BUT PH, KH and CO" are all linked.

with a KH of 1 - your PH will swing 'quite a lot' as the CO2 mixtures fade in and out. - It would be better to have the water better buffered ( higher KH) however this is starting to mess with chemistry and I know i'm not to happy adding stuff to my tank. BUT i believe baking soda will raise your KH.

In the end ,if your adding CO2, you can control what happens.

 

[BobTheDog]

Baking soda will raise KH but this starts a pain in the %$%@#, never ending process. Everytime you do a water change, you have to mix in appropriate amounts of baking soda.

I've HEARD that you can add crushed coral or seashells to your tank and this will increase KH. I believe the theory is that the coral/seashells slowly leach various elements which increase KH. When you do a water change, you will suffer a temporary drop in KH, but it will rebuild on it's own rather then you having to add baking soda. Note that I have ZERO personal experience with this. I have moderately low KH and did some research on the net about methods to increase it. You might try doing your own internet search and see what you can find on this or maybe someone on this forum will know something about it.

Good luck!