Believe it or not, there's no clear cut answer on if you can drink tap water directly or not in Philippines. Among Filipinos (at least in Manila), I'd say 40% drink tap water directly, 20% use some sort of filter, and 40% do not drink it directly
Personally I drink tap water all the time and I have never had any issues
To be on the safe side, I'd advise tourists to avoid drinking tap water directly in Philippines. Even if many locals drink it directly, we're used to it. It is quite safe, but it might still upset your stomach
Instead, filter it, boil it, or just use bottled water which is cheap and widely available
Likewise, do not use direct tap water to make ice that you will consume it later. Use filtered, boiled or bottle water to do so. When you're out and served ice, more upscale restaurants will generally buy ice from manufacturers which adhere to safety standards so you shouldn't worry. But if you're going to smaller restaurants, ask them where their ice come from
However, using tap water to brush your teeth is perfectly fine