What ph do keep yours at...Also my tap ph is about 8 and so far I'm having problems getting it to drop..I've had mine going for a couple weeks and it's only down to 7.6..
I use a pH controller and really like it.
There are two things to work with to inject enough CO2 to lower the pH reading in the tank. First, you have to be sure you have the regulator and needle valve set high enough that it is able to inject enough CO2 to reach the pH you're wanting. One bubble per second won't work. You have to dose more than that regardless of whether you use a pH controller or not. So that's the first step.
The second step is to set the pH you want. Usually, about 1 point drop (from 8.0 to 7.0) is said to dose around 30ppm which is a good target. However, I would not simply set the pH controller to 7.0. Instead, try 7.4 (since 7.6 isn't harming your fish). Wait at least one night to make sure your fish are fine. Then drop it to 7.2. Watch again. If all is good, try 7.1. Then, 7.0. I managed to get mine set at 6.8 pH, starting with an 8.0 pH. However, I was also fighting BBA so I had a strong need for cranking it up.
You want to dose as much as the fish can tolerate. So keep inching it down until your fish show signs of stress (hanging out at the top because the CO2 depleted the oxygen in the tank). At that point, raise the pH setting up a notch and watch again. Eventually, you'll be able to find just the right settings to dose a high level of CO2 without harming your fish.
I strongly recommend a drop checker so you can get a visual idea of how much CO2 is actually in the tank. I got a double check drop checker since it has 2 bulbs, one for the normal solution which will change colors with the pH and a second one that simply has the green color you should try to match.
I have managed to get my pH drop checker to turn more yellow than green. I find this to be a really good setting for my plants, and my fish don't seem bothered with it at all.
Once you get it set up and adjusted, you'll know just how to adjust it in the future. It's just that starting point when you really need to learn the ins and outs of your tank and fish.
Also, do not forget to clean your probe. Calibration is a breeze. Just get some pH 7.0 calibration packets. Open one and put the bag in something to hold it up (I use a glass). Put the probe in and check the reading. If it's still 7.0, rinse and use. If it's off, do a quick adjustment to correct the reading to 7.0. Rinse and use. The whole process takes less than a minute.
