How to turn your green pool blue - a rite of passage to manhood
Step-by-step guide from a man who keeps forgetting how to do this every time.
Most of you were probably expecting my first post after Joa was born to be something profound about raising a newborn. Truth is — it's been 3 weeks, and mostly it feels like he's teaching us how to raise him.
What I can actually help with though, is something that's not really a rite of passage into dad-hood, but a rite of passage into manhood: turning your green pool blue.
I've had to do this about 5 times in the last 7–8 years, and somehow I forget the steps every single time. So I'm writing this down for future me (and hopefully you).
Before we start: if you don't have a pool, don't get one. If you have one, fill it in.
Just kidding. Mostly. Having a pool is a pain 90% of the year but on a 40°C Cape Town day there's nothing better. And I'd like Joa to grow up splashing around in one.
Here's what's actually worked for me:
Step 1: Test your water
Buy yourself an HTH Pool Test Kit from Builders. Test pH and Total Alkalinity (TA). If your pool is green, chances are both are low which means your chlorine isn't doing its job, and you've got algae.
Step 2: Fix your alkalinity
Get a few kg of HTH Alkalinity Up from Builders. Follow the dosage on the pack for your pool size. You want TA between 120-160 ppm. Pour it in on the deep side with the pump running, let it circulate 24 hours, then retest.
Step 3: Shock it
Once your levels are right, add HTH Super Shock. Shock it in the late afternoon (sunlight burns off chlorine). Wait 24 hours. Your pool will still look green — that's the dead algae. Also pour in some HTH Green Algaecide around the sides to help break it down.
Step 4: Add flocculant
Here's the trick most people miss. Your filter can't catch the tiny dead algae particles, which is why the water stays green. Mix HTH Flocculant or BlueChem Alum Flocculant in lukewarm water, pour it around the sides. Run the pump on circulate for 4–6 hours, then turn it off and let it sit for 24–48 hours. Everything settles to the bottom.
Step 5: Vacuum to waste
Top up the pool first — you're going to lose water. Set your filter to "Waste" and vacuum the bottom. All that settled algae gets dumped out instead of clogging your filter.
Step 6: Refill and rebalance
Top it back up, retest everything, adjust. Give it a day to clear up.
There you go. A guide written by someone who's done this enough times to finally write it down. Future Eugene owes me one.