Fishbowl Solar Distiller Outside Water Feature

Introduction: Fishbowl Solar Distiller Outside Water Feature

About: team humanity lamingtons for lemmings left wing solar cooking challenge

Fishbowl solar distiller for the garden...

This is a simple solar distiller for gardening use.
Made from recycle shop bits and pieces that are lying around.
Food safe distilled water is a whole different ball game, this distiller is a passive water feature to use for watering your delicate plants... or perhaps an art or construction project that needs distilled water.,.
Makes variable quantities of distilled water from evaporated source water and condensation running down into the bowl.

You will need:
One big glass fishbowl
Base aluminium bowl or tray

Glass pie dish or white ceramic dish larger than rim of fishbowl

Black ceramic bowl
Optional statue or metal upright

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: Charcoal and Water Placed in a Black Ceramic Bowl

You will need


Black ceramic bowl
Glass or white ceramic base dish
Large Fishbowl
Cast iron or bronze figurine
Aluminium wide bowl or tray

Some extra reflectors or mirrors are optional

This is a simple distiller for the backyard for making small amounts of distilled water for gardening use.
I use the distilled water for watering Venus Fly Trap plants, ferns mosses, that require high humidity and low nutrients.
The lip of the black ceramic bowl needs to be higher than the lip of the outer bowl.
If it rains heavily the lower bowl is going to fill and overflow.
You don't want it to backflow into your evaporation bowl.
If you use an aluminium wide bowl or tray under a glass blow it acts as an extremely effective reflector.
On sunny days when the temperature is over 20C this aluminium tray underneath and the greenhouse effect will be enough to maintain evaporation.
Additional reflectors will increaase the speed of evaporation. Place the bowl near a light coloured wall or aluminium shed that faces the equator, instant reflector.

The charcoal breaks up water molecules surface tension. Floating charcoal will draw and separate water molecules by capillary action.
The charcoal will dry completely and a ring of salts and metal salts and sediment will form in your evaporation bowl.
Every few weeks or months change the charcoal and rinse out the bowl. The sediment needs to go under trees or in the garbage disposal as it will be concentrated from your water supply and shouldn't go on a veggie patch or into compost. Worms don't like charcoal anyhow.

Step 2: Add a Cast Iron or Bronze Figurine to Capture Heat

About using charcoal
Half burnt charcoal is going to float. It is very lightweight and has air trapped in it.
Completely burnt and crushed charcoal is going to sink to the bottom and stay there.
If you are not fussed either way doesn't matter.
If you are needing water with no splashed bits of floating charcoal, I suggest you grind it down with a pestle and mortar and get the air out of it, so you get a 1 cm to 1 inch layer of charcoal in the bottom of the bowl.
Skim any floating bits of charcoal off to avoid further annoyance.
Charcoal in the water increases the temperature of the water faster than water alone, as it increases the surface area of the water in contact with a warm surface.
The charcoal and water are going to warm up and evaporate from a surface temperature of about 50C degrees.

Adding a statue

Any metal standing figurine or standing block of metal if you don't do statues, is going to capture additional heat from the sun. It will warm up the water more than the shadow it casts by it. In winter months the statue may not even cast a shadow into the bowl at all, which is even better.

A metal statute isn't necessary, it is an embellishment that just works and is a great way of using a broken or otherwise useless household object. It also holds down the bowls in a stiff breeze.
Finally, a statue is a deterrent to small children to try and get their fingers under the edges of the fish bowl as most are taught from a young age not to handle ornaments.

Step 3: Step 3: Fishbowl Cover

Cover with the biggest fishbowl you can find

Add a fishbowl over the top upside down.
Note condensation on the inside of the bowl.
The larger the fishbowl the better.
This one sits inside the rim of the base bowl.

If you want to make a bigger version overall, a fibreglass bath can be used, angled by the latitude where you live to the equator, evap bowls put on a few bricks to bring them into the full glare of the sun all day, and a sliding glass door or glass tabletop, or taped on plastic put over the top.
A hose from a tap and stop cock from a cistern can be used in the evaporation bowl to automatically refill the evaporation bowl to a required depth.
Placing dark porous bluestone volcanic rocks in the evap bowls with charcoal will draw water up and heat it efficiently. The bath can be angled to drain to a bucket or some ag pipe taped on to drip water nearby plants.
Just experiment with whats around.

Step 4: Step 4: Fishbowl Solar Distiller Results

Collecting your distilled water

The best time to collect your distilled water is in the morning before the sun is on the fishbowl.
The results should be a proportion of the water in the evap dish has evaporated.
If it hasn't evaporated at all on a sunny day there might be something wrong such as the fishbowl rim not fitting inside the lower bowl.
Pick the evaporation bowl up out of the lower bowl and drain the contents.
In this picture a 10 inch pie dish collected approx 100 ml of distilled water in 24 hours.

Thanks for your time reading through this Instructable.
Please post comments and photos if you sent one up anytime.
All suggestions and improvements welcome!

Be the First to Share


    • Toys and Games Challenge

      Toys and Games Challenge
    • Backyard Contest

      Backyard Contest
    • Silly Hats Speed Challenge

      Silly Hats Speed Challenge