Ph climbs hourly. Unsure what I’m doing wrong

Hey man it’s imperative that you cover the water in the res otherwise you could have algea growth in the water. That’s the last thing you want... also PH climes when using air stones, you can turn them off await 5mins and watch the PH fall again. It’s best to bubble your water outside the res for 24hours if using tap water then add to the res. Using only a submersable pump to “flume” the water (creating a flow of water to the surface like a mound of water just catches the oxygen from the air and brings it into the water without using bubbles. Hope that helps! :D