Co2 and pH

[elilk]

Hi guys,
Just wondering if anyone knows whether when using diy co2, your pH will stabilize after dropping, or does it keep dropping? I'm using API test kit but the lowest pH it shows is 6, and that's what I'm at so I need to know if it is going lower but I cant see it..
I'd like to put some endlers or shrimp in there eventually but need to stabilize the pH first.

pH was 7.2 before Co2 started
2.5 gallon bowl
freshly planted with Hairgrass
15 watt flouro 6500k
Seachem Flourish
1.5 litre DIY Co2 1 bbps
GH 250ppm
No fish yet so I'm assuming no ammonia nitrite, or nitrate.

Thanks, Elise

 

[fort384]

pH is going to swing throughout the photoperiod when you are adding CO2 to the water. pH swing due to CO2 addition is not generally harmful to your fish, but if it is dropping below 6, you are getting close to overkill I would say. What is your KH?

 

[gzeiger]

CO2 + H2O <----> H(+) + HCO3(-)

When CO2 is removed from your water, either by coming out of solution and exiting at the surface or being metabolized by plants, what's left is pure water. There is no residual effect on pH. It's controlled only by the amount of CO2 currently in the water (and the other, nonvariable, water conditions). DIY CO2 won't give you an uncontrolled amount of dissolved gas.

It is technically possible to get down below 5.5 with CO2 injection, but it's not very likely in an aquarium especially with the filter running.

Most fish will be perfectly fine at a pH of 6. I'd say go ahead and get them (shrimp too), just be sure to acclimate very carefully. Airline tubing for drip acclimation is probably the best $2 you'll ever spend on a fish tank.

 

[elilk]

Thanks guys,
I don't have a KH test kit but I should probably get one.. Thanks gzeiger, your answer was very helpul, now I understand! (Except the top bit, I never did chem at school I've got some spare tubing lying around too, I never heard of drip acclimation before, sounds alot easier than the old come back every 5 mins and pour some more in!
Cheers,

 

[gzeiger]

The top bit says the same thing as the first paragraph of text, so no worries there.

Drip acclimation is great. You just use airline tubing to make a siphon (hold it underwater in the tank until it's full of water and then hold your thumb over the end as you remove the end from the tank. Put the fish in a bucket on the floor and position the tubing so it flows into the bucket. Then you can kink the tubing and hold it in place with a rubber band, bread tie, piece of string or whatever and adjust the kink until you get the desired flow rate. Once the bucket is nearly full you can net the fish out so you don't get much of the pet store's germ-riddled water in your tank, and top off the tank for a water change at the same time!

You can generally do this pretty fast for store-bought fish since they'll be acclimated to something fairly close in temperature at least to what you're putting them in. I've done 24-36 hour drips with some more fragile wild-caught fish due to winter water temperatures though.

 

[elilk]

I did it yesterday with some plecs and sae in my big tank, so much easier and less stress than the floating bag fiasco! Only an hour though.

 

[gzeiger]

I'm sure an hour would be fine with anything you get from a store.