Practical, research-backed guides on filtering your tap water, shower and bath, what's actually in your city's supply, and the science of hydrogen water. Written in Sydney by the HolyH₂O team.

Most Australians assume tap water is either perfectly fine or that any filter will do. Neither is quite right. Thi...
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Tap filter, jug filter, or gravity benchtop, each works differently and suits a different household. Here's an honest...
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PFAS, 'forever chemicals', have been found in Sydney tap water, near airports, military bases, and industrial sites a...
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A 2024 systematic review of 25 human clinical trials found consistent evidence for hydrogen water's antioxidant and a...
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Bath ball filter, tap-mount purifier, bath filter, same category, different names. Here's what actually matters, how ...
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Renters can absolutely filter their tap water, without landlord permission, without a plumber, and without permanent ...
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Do hydrogen water bottles filter your water? No. A hydrogen bottle adds molecular hydrogen, a filter takes chlorine, fluoride and metals out. Here is why you want both jobs done...
Do hydrogen water bottles filter your water? No. A hydrogen bottle adds molecular hydrogen, a filter takes chlorine, fluoride and metals out. Here is why you want both jobs done...
Can you drink shower water? A shower blends in hot water, and Australian health departments say only drink from the cold tap. Here's why, what to know about the bathroom...
Can you drink shower water? A shower blends in hot water, and Australian health departments say only drink from the cold tap. Here's why, what to know about the bathroom...
Sold as an "ionized water bottle"? Most are hydrogen generators, basic electrolysis bottles or alkaline mineral bottles. Here's how to tell them apart, the five checks that matter and which...
Sold as an "ionized water bottle"? Most are hydrogen generators, basic electrolysis bottles or alkaline mineral bottles. Here's how to tell them apart, the five checks that matter and which...
Melbourne water is soft but chlorinated and fluoridated, so the right filter is about taste and choice, not hardness. See Melbourne water by retailer zone and the best HolyH₂O picks...
Melbourne water is soft but chlorinated and fluoridated, so the right filter is about taste and choice, not hardness. See Melbourne water by retailer zone and the best HolyH₂O picks...
Perth scheme water is chlorinated and, in northern suburbs, very hard. Here's what a shower filter fixes in Perth, what it doesn't, Perth hardness by suburb, and which HolyH₂O filter...
Perth scheme water is chlorinated and, in northern suburbs, very hard. Here's what a shower filter fixes in Perth, what it doesn't, Perth hardness by suburb, and which HolyH₂O filter...
Not every shower filter removes chlorine. Here's which filter media actually work in a hot Aussie shower (KDF, catalytic carbon, vitamin C), how much chlorine is in our tap water,...
Not every shower filter removes chlorine. Here's which filter media actually work in a hot Aussie shower (KDF, catalytic carbon, vitamin C), how much chlorine is in our tap water,...