freshreef

I never used ph controller and never had air stone in my planted tank. now im setting up a new 100G tank with aquasoil and soft water (gh 3, kh3 )and installed PH controller. before any co2 injection the PH is 6.3-6.4 (reading from the ph controller) i set the controller to shut off the co2 at 5.8 (i know that by the kh/ph table its a lot - but i dont trust it). i would like to add air stone as i would like to introduce a few species of shrimps and heard they need good amounts of oxygen .
Now my question is that : if i add air stone to the tank during dark hours - will it give more oxygen to the water? i think its like driving a car with one leg on the brakes and one leg on the gas... but still want your opinion?
Will it make the controller work harder to achieve the desire PH (and co2 levels)? i dont mind loosing CO2 for nothing but would like to keep my shrimps alive!

magicmagni

I don't think that the levels of CO2 and O2 in the water are dependant on one another. I mean that if the C02 levels are high it doesn't mean the O2 levels are low.

I can say from personal experience that running an airstone is not a problem. I run one 24/7 with not problems except for loosing a bit of C02. Fish seem much better and active in the morning. They are not gasping for air at the surface!

If you want to check your water for any buffers you can do that easily. Just take a water sample and let it sit 24 hours. Take your ph and KH measurement and it should be at around 2-5ppm c02 on the chart. If not then you have an idea of how much "off" the chart is for your application. BTW make sure you've calibrated your probe recently and that it is isolated from electronics such as lights and pumps so that you get an accurate measurement. This may not be so practical, but sometimes it can throw off the reading so at least take a reading with everything off and then on to note any differences.