Fish Tank Plant Cloner

About: I am an exhibit developer at the Exploratorium.

 Modify a Marineland brand "Eclipse" fish tank filter to be a mini plant cloning unit.*

For this mod, you will need a hack saw or jig saw to cut a hole in the lid, a bag of filter floss, a pair of scissors, and two foam sponges.  You will also need two light fixtures and compact florescent bulbs to give your cuttings adequate light. If your tank is in bright light you won't need the fixtures, but keeping a fish tank is bright daylight promotes lots of algae growth.

*This instructable will show you how to mod your filter, but does not cover how to set up or maintain a home fish tank.

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Step 1: Aquire an Eclipse Filter

 The Marineland brand Eclipse filters are common "all in one" filtering and lighting systems for aquariums.  They can be found used on eBay or possibly in a local thrift store.  They are also readily available online.  I already had one on my 20 gallon fish tank, and liked it, but did not want to keep buying the filter cartridge replacements.  So I now use plants to clean my water.

Step 2: Remove the Filter Cartridge and Lid

 First step is to open the lid and remove the blue filter cartridge.  Next, slide open the two tabs at the back corners of the lid and lift the lid out.  

Step 3: Mark and Cut the Hole on the Lid

 Use a marking pen to trace out a  U-shaped hole in the lid that will give you access to the tray that holds the filter cartridge.  This tray will hold your clones.  You want to cut out a hole that allows access to the entire tray but still covers the pump inlet on the left and the biowheel on the right.  

Now use a jig saw or hack saw to cut out the hole you marked.  

Step 4: Replace the Filter Cartridge With a Shallow Bed of Filter Floss and Sponge

 Now that the tray is empty, you can fill it with a small amount of filter floss.  This is the white fluffy stuff sold in fish stores that filters particulates out of aquarium water.  You only need a layer about 1/2" thick.  Have the filter running when you do this so you can get it wet and that will make it easier to get it in the tray nice and evenly. 

Next, take your two (or more depending on your model of Eclipse filter) foam sponges and cut slits from the long edges into the center.  These slits will hold your cuttings upright.  Place the sponges into the tray on top of the filter floss.

Step 5: Replace Lid and Add Plant Cuttings

 Replace the lid and secure by sliding the tabs into place. Now you can take a few cuttings and slide them into the slots of your sponge.  Be sure the end of the cutting reaches down into the wet filter floss.  Experiment with different types of plants.  Spider plants can grow quite large in the this set up so be prepared to cut them back or divide them.  I have had success with lavender, mint  and rosemary, too.

Step 6: Mount Your CFLs

 Next, be sure to give your cuttings the light they need to thrive.  I used two 9 watt bulbs in clamp fixtures with metal reflector shades.

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    7 Discussions


    9 years ago on Introduction

    Cool. Some more pics of before and after the cutting of the lid would be helpful. Do the plants filer as well as the carbon in the original cartridges?

    And like Nizerbean I'm confused as to where the cloning is happening.

    2 replies

    Reply 9 years ago on Introduction

    The cartridges are probably necessary if you have a ton of fish in your tank, but I only have guppies, and I also have live aquatic plants in the tank.  I never have to clean this tank, not even scrape algae off the glass, so I think the plants I have in it are doing the work for me.  Also, I swapped out the florescent fixture in the hood with LED puck lights.  They use way less energy and keep excessive algae from growing.  The cuttings could probably root in indirect daylight, but I have no windows so I use a couple 5 W CFLs instead.


    Reply 9 years ago on Introduction

    I will add more pics as soon as I get back to my cloner.  I'm out of town at the moment.   


    9 years ago on Introduction

    Is cloning the right word here? Are you getting your plants to root or are they somehow replicating themselves, maybe this is a new term I am not familiar with, but with my fish tank I just stretched netting across the top and stick the plant cutting in the water (the netting holds it upright and the big leaves stay dry) until it roots and then I plant it in the ground. Is what you have wonderfully shown here the same thing? Sort of?

    1 reply

    Reply 9 years ago on Introduction

    Rooting cuttings taken from a single plant is replication without sexual reproduction, so the new cuttings are genetically identical to the mother plant.  Cloning is just a fancy term for rooting cuttings.  Gardeners have been doing this for ages, so it's not just the biotech companies who have this technology. Which is great for gardeners who want to use this technique!


    9 years ago on Introduction

    I have done the same thing before. But just for cloning, you can take the plant cutting and just stick it into a water jar, depends on the plant species, some will grow roots in a few week, some just rotten away.

    I also have a bigger fish tank, i used those suction basket, and fill it with some sand and stick it inside the fish tank wall, this way, it can get both water and lighting inside the fish tank. Adding 2 additional lighting source just for the plant, seem a little wasteful to me.