By Sarah Chen · environmental engineer · water, waste and everything that flows downhill
“After wasting three bags of lime on my WA bore, I learned one gram of sulfur neutralises a litre of pH 9 water every time.”
— Sarah. Every litre accounted for.
ArticlesCalculatorsSite PlannerShopOff-grid water in Australia? Acidic? Alkaline? Fix it. No fluff. Here's how.
Off-grid water in Australia? Acidic? Alkaline? Fix it. No fluff. Here's how.
Use when pH is below 6.5 (common in rainwater tanks after heavy rain). Sulfur oxidises to form sulphuric acid, which then reacts with carbonates to raise pH. Slow but cheap.
How: Mix 10g sulfur powder per 100L water in a bucket. Stir for 24 hours. Then add to tank. Test after 48 hours. Don't dump it straight in.
Blunt tip: Sulfur doesn't work in hard water. If your tank's got limescale, skip it. Use lime instead.
Calcium hydroxide (slaked lime). Works faster than sulfur. Use when pH is <6.5 and you need quick results.
How: Start with 5g per 100L. Dissolve in a bucket of water. Stir, wait 10 mins, then add to tank. Test after 24 hours. Overdo it and you get pH 9+ (water turns slimy).
Blunt tip: Wear gloves and goggles. Lime burns. If you're not wearing them, stop. You'll regret it.
Use when pH is above 8.5 (common in bore water). Food-grade citric acid or phosphoric acid. Not for acidic water.
How: Dissolve 10g citric acid in 1L water. Add to tank. Test after 2 hours. Repeat if needed. Never add dry powder to tank.
Blunt tip: Citric acid is safe, cheap, and you can buy it at Coles/Woolworths. Don't waste money on "special" acid neutralisers. This works.
Test your water FIRST. $15 pH test kit from Bunnings. Guessing is how you ruin a tank.
Always pre-mix in a bucket. Never add dry chemicals to your tank. You'll get a sludge storm and a headache.
Start small. Add 1/4 of the dose. Wait 24 hours. Test. Then add more. Over-adjusting is easier than fixing.
For big tanks (500L+), use a dosing pump. But if you're off-grid, you're probably not spending $200 on a pump. Just do it manually.
If your water's consistently off, get a proper water test. $30 from a local lab. It's cheaper than replacing a tank.
Bottom line: Sulfur = cheap but slow. Lime = fast but needs care. Citric acid = only for alkaline water. Test. Mix. Wait. Test again. Done.
While many off-grid projects are achievable as DIY, certain situations require licensed professionals:
Always check local regulations and obtain necessary permits before commencing work.
Worth a watch: 12 Australian Towns Where You Can Live Off Grid For Practically Free · Loving Australia