You are here:

Carnivorous Plants/humidifier algae


I got a growing problem ,but its more of a how do i not grow. I run a humidifier all day every day,its how i get my nepenthes to grow pitchers all year in my house without a greenhouse,and keep the pitchers without the top half dieing. The humidifier keeps getting green algae in it,but then i realized im growing it with the lights.i have ten cpf,26 watt. Im looking for a humidifier that does not have a clear tank,but until i find 1, i was going to put something around it ,like a towel or aluminom foil to block the light.but is there anything else i can do to stop the algae growth,thx for all the advise.i ve learned more in 3 months of reading your answerse on allexperts,than i did in three years.thank you,jim

Hi Jim,

I assuming this is an ultrasonic humidifier with the usual clear tank.  One method I've run across is to use distilled water in the tank.  If you clean the tank well with bleach first, then use distilled water after that, the water has no food at all for the algae, so it can't grow.  

We have a ZeroWater water dispenser tank type filter, and we've noticed that the purified water never gets algae in it.  ZeroWater filters take everything out of the water, so it is very close to distilled water.  The top part where you add the water gets algae all the time, and we have to take it apart and clean it about once a month.  But the bottom part of the tank where the purified water is never gets algae.

Let me know if this works for you.

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 8,800 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!

©2016 All rights reserved.