That popping and thumping is sediment buildup at the bottom of the tank. The gas burner can't transfer heat evenly through the sediment so the water boils and creates steam bubbles that compress as they rise through the cooler water above. Good news is it is not damaging. You can try draining the sediment but it is not urgent. 🙌💧 #HomeImprovement #HomeRepair #WaterHeater #DIYHome #HomeTips #PlumbingTips #LearnOnTikTok #HomeHacks #FirstTimeHomeowner #MrFixIt