# diy CO2: questions about preventing overdosing, aeration, pH, & hardness



## Akeath (Mar 7, 2011)

I'm thinking about making some diy co2 and connecting it to a Hagen ladder for my 10 gallon future Cherry Shrimp tank.
One of the main reasons I'm considering this is for the pH changes, my water is 8.2 pH, 11 gH, and 71 ppm kh. I want to get it down to 7.5 pH or below for the Cherry Shrimp, and would rather do this in a way that didn't color the water like peat would. In addition, I have 2 10 watt 6500 K cfls, and since I've added these I've been having more algae issues, and I've heard that adding CO2 will help the plants out compete the algae. I'm also adding some fertilizer, carefully chosen for its lack of copper, I'm using Kent's pro plant and Seachem's Iron. Right now I have a rather odd grouping of plants, Amazon Sword, Wisteria, Java Fern, and Pennywort. I'm going to completely redo the scape before I get the shrimp though, and will have Christmas Moss, Weeping Moss, Taiwan Moss, Downoi, and Marsilea minuta. Perhaps some other types too.

I'm very nervous about overdosing the CO2 and hurting the shrimp. I know a lot of people recommend turning the CO2 off at night to prevent this, but since I'm relying on it to keep my pH at a shrimp-safe level I'm concerned that the pH will swing too much if I do so or get too high again. I'd like to know if having an air stone on just at night would also cause a pH swing, or if diy CO2 by its very nature causes pH swings. Since the shrimp are definitely the priority in the aquarium I would rather waste a bit of CO2 than risk and overdose, and I was wondering if having an airstone on all the time would be an okay solution. I also have a hang-on-the-back filter that has an adjustable flow, which I could use to aerate a certain amount. I was also thinking about buying Seachem's CO2 indicator and keeping an eye on things with that. Would any of these precautions be effective? Which should I try?
Also, would CO2 make my water too soft for shrimp? Cherry Shrimp prefer slightly hard water, would the unchanged gH be the important measurement for that, or would my water be considered soft with the addition of CO2?
Thanks!


----------



## funnytrash (Sep 5, 2010)

personally you would need a lot of diy c02 to actually change somethings so im pretty sure one diy co2 wont change much.


----------



## Diana K (Dec 20, 2007)

Your KH is low. 71 ppm is only about 4 German degrees of hardness. This means that you will likely see pH changes with the CO2, as long as it is well distributed. Not extreme changes, 4 degrees of KH does help keep the pH stable. 
But pH over 8 with such low KH suggests the water company is adding something else to raise the pH. 

GH is 'soft' or 'hard' water. Not pH. 
"11 GH" Huh? What units? Is this reported in degrees? If so, this is pretty hard water. 

A 2 liter DIY yeast/sugar CO2 generator on a 10 gallon tank can add a significant amount of CO2 to the water. 
The ladder does not mix the CO2 with the water at all. There is a slight rise in CO2 right next to the ladder, but it needs to be spread throughout the tank. 
I would put a small powerhead (Koralia Nano) above the ladder to really spread the CO2 through the tank. If you find it is doing too much (lowering the pH more than the shrimp like) you can move the power head until it mixes the water just right. Really, I would skip the ladder, and just release the CO2 right under the power head. The blade in the power head will mix the CO2 better than the ladder, then send it throughout the tank. 

The only way to get the answers to these questions is to try it on your own tank. Each tank, each set up varies a bit, no matter how you make it like another, and minor changes in equipment choices and set up can mean big differences in effect.


----------



## gh0ul (Jun 5, 2011)

I am experiencing Super hi levels in my 29 gal planted using DIY CO2. I'm using one of those stainless 
steel 750ml Water bottles for the generator and a baby food jar for the bubble counter/alcohol filter.
For the Co2 distribution I have a pond pump with a small plastic container hooked to the output firing
water downward with the CO2 being fed into the plastic "reactor" thru a small airstone. I have a small
piece of foam attached to the bottom that only allows the smallest of bubbles to escape and this setup
really saturates some CO2 into the water!! After about 30 mintes I get 1 to 3 bubbles per sec for a day or 2 then it slows to 1 every 2 secs. Looking thru the tanks side you can see a mist of tiny CO2 bubbles
all over the tank. Very effective. 

I've been using this for 3 weeks 4 days now. after 2 days my levels went to 24ppm, (pH = 6.8, kH = 5)
So Im getting a bubble every 2 to s secs, running fine, fiaaled out after 5 days and I redid the Yeast
mixture..... THe levels sky rockested to 84 ppm in one day!! Holy cow! 

How are you supposed to control DIY Co2??? Is there a tried and true method? I just open the cannister and waste the co2 till the levels drop. It's a pain. But after 3 weeks, My god.... The plant 
growth is astounding!!! I swear some of the stem plants are growing a half inch or more a day.... 
but.... Its a constant game of watching the levels. 

Anyone know how to control this? Should I start with a strong mix, get to 25ppm, then change to lighter mix of yeast/sugar, say half what I started with to keep it low. Maybe a bubble every 3 to 4 secs to maintain the level?


----------



## Se7eN (Sep 23, 2010)

Before I changed to pressurized, I had 6 two liters on a 20 gal and my plants were growing like crazy. I never lost any fish or shrimp. Just got tired of messing with it and ended up going pressured about 2 years later.

With diy on a 10 gal, you would have to have like 4 bottles going at one time to do any damage, I had all mine on the 20 gal alternating weeks so I was changing one every week.


----------

