You are here:

Carnivorous Plants/Zero Water Filter - when to replace?


Hi Jeff and Jacob,

Based on your recommendations I use a Zero Water filter for watering my carnivorous plants. I'm wondering if you have enough experience with Zero Water filters to give me some insight. The manufacturer says to replace the filter after the filtered water reaches 6ppm or more. As far as I know, carnivorous plants should be happy with anything under 70ppm or around there. My question is, is there any danger in continuing to use the filter until the water reads 70ppm?

I'm not going to ask the manufacturer whether their filtered water is safe for carnivorous plants after it exceeds their recommended ppm amount. But I thought I'd take a shot in the dark to see if you guys have experimented with this. Thanks either way, and thanks for consistently taking the time to answer so many questions online.

Hi Mark,

Not sure I have a good answer for you on this one.  We use a ZeroWater twin filter, water dispenser type filter in our home for drinking water, and then water our cp houseplants with the water.  We replace the filters when they get to about 10-20ppm.  The water starts to get a distinctly "fishy" smell when the filters are shot.  What I don't know is what compounds are being left behind, and what isn't when the filters are full.  I do know that the TDS rises sharply once the filters expire, so even when you reach 70ppm, it won't be long before the TDS is much higher than that.  You might get a gallon or two extra, but not much more than that before the water isn't safe anymore.

Good Growing!

Jeff Dallas
Sarracenia Northwest

Carnivorous Plants

All Answers

Answers by Expert:

Ask Experts


Sarracenia Northwest


If your carnivorous plant is showing poor growth, discoloration, abnormal leaves or possible infestation, the expert growers at Sarracenia Northwest can help! They have a great depth of experience dealing with diseases, pathogens, and abnormal growth in carnivorous plants.

Before submitting your question, please read their care guides on their main website. Many issues can be addressed by simply adjusting your growing conditions as recommended in the care guides. Click here to read the care guides.

Over 9,000 questions answered since 2005!


Jeff and Jacob are owners and growers of Sarracenia Northwest. They've been in business since 1995. Watch their professionally produced DVDs, Grow Carnivorous Plants. It is a three-volume set that covers all aspects of carnivorous plant care. They literally show you how to be a successful grower!


No terrariums. No myths. No nonsense.
Just the straight facts from guys who grow and propagate
thousands of carnivorous plants each year.

Our focus is to help help growers diagnose a specific plant problem and offer solutions. For example:
  • Why is my sundew not producing dew?
  • Is now a good time to divide my Sarracenia?
  • Why are the traps turning black?
  • What's a good substitute for perlite?
  • Why didn't my seeds germinate?
  • How do you deal with pests?
  • Can you identify this carnivorous plant for me?
We no longer answer general, how-to questions that are already posted on our website or demonstrated in our DVDs. For general plant care, please read our care guides:

For business questions:

Youtube Facebook
Follow us on Youtube and Facebook!

©2017 All rights reserved.