As a grand finale to our biology unit, we made desktop aquatic biospheres. The process that I will give links for in this post is for if you’re doing this for a large group (20 kids). You can most certainly make one of these for your household even more easily than doing it for a large group.
Similar to the terrariums, we set this up assembly-line style and it went great. It’ has now been a couple of months and our biosphere is still going strong. We lost one snail, saw a bunch more be born and grow and our little shrimp is very much alive and well.
· A 1-quart glass mason jar (not plastic – plastic can leach chemicals into the water)
· Plastic containers for mixing and for a holding tank (we used Walmart utility buckets)
· Aquarium with aerator if you need to hold the live animals for a group project
· Tap water
From an aquarium store:
· Aquarium gravel
· Tap water dechlorinator
· Glass or ceramic ornaments, seashells
· Freshwater minerals such as “Kent Freshwater” or “Cichlid Salts”
· Freshwater cleaner shrimp or similar (eats algae and can tolerate high pH levels)
· Two small snails (we used bladder snails)
· Eight stem inches hornwort or elodea
· Duckweed (Lemna) if you can find it
· One TBSP powdered calcium carbonate (primary pH buffer)
· Algae wafers (only if you need to feed the animals while waiting for group project)
From a local fresh water source or pond:
· Algae or water plants
· Pond water
· 1 to 2 TBSP pond sludge – should contain small animals, bacteria, and microalgae
Hope you make your own and send us some pictures!