DIY Co2 causes PH crash

[chooks]

I added a ceramic co2 diffuser to my DIY to increase the amount of dissolved c02.  Apparently it works too well, as my PH hit the floor(carbonic acid?).  Is there a way to slow the co2 output(less yeast?/champagne yeast?), or should I be using some sort of PH buffer?

Here are the specs:
25 gallon tank
2 litre DIY: 2 cups sugar, 1 tsp. yeast

Thanks!

[dattack]

You can probably add more plants or place an air stone at night when the plants are not using the CO2.  Most pH crashes occur in the morning because their are no lights for plants to use the CO2.  Is your tank heavily planted?  and I was wondering if a diffuser is just as effective as a reactor and how much did it cost you?  I have a reactor and a diffuser kinda looks cool with their fine bubble.

[chooks]

Thanks Dattack,
Yeah, my tank is fully planted.  I'm not sure what you mean by reactor?  Just an airtube?  My co2 setup has been throught a few phases.  First I let it leak straight out of the tube, but I wasn't getting good results(The bubbles floated to the surface too fast and very little co2 dissolved into the water).  Next I tried an airstone, but it clogged, worked erratically, and started to dissolve!  Now I'm using a ceramic diffuser with a built in bubble counter(don't remember the brand though..) and it works awesome.  Most of the bubbles that come out of it don't even reach the surface, they completely dissolve into the water. All of my plants have tiny bubbles of oxygen under their leaves too.  The diffuser was 15 bucks at the fish store, I highly, highly recommend it if you need more CO2 ion your tank.

[Fish Monger]

A fella that I work with uses DIY CO2 (the Bruce Hallman method), and his setup works like this:

Airline from Soda bottle to a check valve. *The check vavle has an airline from it to a typical airline valve, then airline to the tank. *He uses the airline valve to "regulate" how much CO2 goes into the tank. *He says it builds up a little pressure in the bottle, but if the airline is siliconed into the bottle good it won't pop off.

He also uses the valve to turn off the CO2 at night as the plants respire during this time. *This is the type of CO2 I'm going to use when I get my planted tank started in late August. *He has *had pretty good success with it over the past year or so.

[chooks]

Thanks fish monger,
Hopefully the pressure won't build up too much and make the tubes pop off. I'm trying to think of some kind of idea for a pressure sink.  When the check valve is turned off some kind of reservoir fills up w/CO2 & empties when the valve is tuned back on.  Maybe I'll try using a thick baloon.  Hmm...Maybe I should let it be.

[SegaDojo]

i'm surprised that nobody mentioned the kH requirement.

Chooks... whenever you add CO2 to your tank, you kH values MUST be 3 degrees of hardness or higher.  The kH acts as a chemical buffering agent, helping to stabilize pH.  Anything lower than that will put you in a risk of a pH crash.

I prefer using crushed coral (~1-2 tablespoons per 10gallon) in a media bag, and run it through the filter.  However, for emergency situations (as you may call this) you can add baking soda.  How much? i'm unsure... perhaps someone else who has more experience using baking soda can answer this.  My best GUESS is a teaspoon per 10g..

[Matt Nace]

I have read about baking soda as well for this. I saw it at 1tsp for 8 0z of water, mix it to the water after a waterchange in a seperate bucket..not right in the tank.

Sega's guess would be a lower dose which I would try first.

Also for now remove the Co2 until your KH is more stabilized.

Do NOT ever stop or slow down the DIY CO2 bottles. If you do your little plastic bottle could burst. The pressure is more than you think when you block it. That is why you should never use an airstone to diffuse the Co2. Co2 (DIY) can create little pieces of gunk which can clog and block your airstone causing your bottle to explode. There are many stories at thekrib about that.

Fish-monger...your buddy is asking for it by blocking it at night. look out even if he hasn't had a problem yet.

For night time the best thing(I forgot where I read it) is to put a timer on an airpump and have an airstone come on after lights out.

[Fish Monger]

I found out how many DIY bottles I'd need to use for my 75, and I'm not gonna go that route any more. *I'm a little too lazy to be fuzting with three or more bottles, so I think I'm gonna serve as a guinnea pig and try the Carbo-Plus CO2 system. *For info on it, go to http://www.petwarehouse.com and look in their section that has all the CO2 stuff.