Tea-coloured water? Two-step process can filter out tannins
Q: How can I get rid of the discolouration of tap water at my house caused by tannins?
We have a 38-metre-deep well and water quality has decreased over the past six years.
Over the last three years, we’ve done a shock treatment, changed the well cap, installed a water softener, put in a reverse osmosis system for the kitchen faucet, installed a carbon filter, plus added a UV system and filter.
Two weeks ago, I had a chlorine injection system added, but the bath water still has a light tea colour compared to the water at the kitchen sink that comes from the reverse osmosis machine. Any suggestions?
A: It certainly sounds like you’ve got all kinds of equipment at your place. I can suggest a few things based on my personal experience getting rid of tea-coloured water at my house. It’s just too bad I didn’t hear about your issue before you bought all that equipment.
As you mentioned, discolouration of water is often the result of a family of naturally occurring substances called tannins. In my experience, the best way to remove tannins is with a two-step process. First, an oxidizing agent is added to the water, then the water is filtered through carbon.
You mentioned that you’ve got a chlorine system now, and though chlorine is a reasonable oxidizer, it’s not nearly as powerful an oxidizer as ozone or hydrogen peroxide. At my place, we get our water from a drilled well that does have noticeable tannins in it when we get wet weather.
To combat this, I have hydrogen peroxide injection (about 25 parts per million in the water), followed by a whole-house carbon filter. This combination removes all tannins in the water, even when tannin levels are high enough to cause quite a noticeable discolouration of water in a toilet during spring or when we get heavy fall rains.
I’d try and find a water treatment specialist who’s familiar with hydrogen peroxide or ozone technology. They may want to run some chemical tests on your water first, but I think you’ll find either of these options offers a complete solution.
A Canadian company called Aclarus (aclarus.ca; 888-7058801) is a world leader in ozone technology, and their residential home systems don’t even need any ongoing supplies.
The ozone that gets injected into the water is synthesized from the air itself. The hydrogen peroxide system at my house only costs about $100 per year for purchased peroxide.
Both ozone and hydrogen peroxide are also very effective at oxidizing iron and sulphur, allowing both these substances to be filtered out using a wholehouse carbon filter.
Q: Do I need to screw subfloor tiles to the concrete floor in the basement I’m finishing? I bought some DRIcore panels for the floor, but I’m getting mixed advice on whether these should be fastened or left free floating.
A: The short answer is no, you don’t need to fasten any kind of subfloor panels to your basement floor. That said, your concrete floor really does need to be quite flat to support the panels properly. Some floors are flat enough on their own, but it’s not unusual for workers to be sloppy when it comes to finishing concrete basement floors. Any dips or rises in the concrete will allow the subfloor tiles to wiggle and rock, causing problems later. I suspect the advice you’ve heard about needing to mechanically fasten subfloor tiles comes from someone who had an uneven basement floor.
Levelling could require the use of levelling compound, but maybe not. The DRIcore panels you mentioned are made to work with special shims (also made by DRIcore) that allow you to compensate for small errors in the concrete.
Steve Maxwell coaches people who want to finish basements the right way. Learn to avoid the five most common basement-finishing errors at baileylineroad.com/ finish-a-basement-right.