It's planned to put in a few rodents in the biosphere when the CO2 is stabilized under 400 ppm.  The rodents need water and something to eat.  Currently a vegetarian diet it planned for them.  Water needs to be available for them too.  This is done with a beaker where dehumidified water is purred into before it overflows into the soil.  

 

There are two identical tanks, one is used for hosing the inhabitants while the other has recovering plants after eaten by the rodents.  It's a crop swapping method.  A 1 oz. mouse will eat around 3 to 4 grams of plant material and water.  That's already has been tested and the plants have been picked.  It's important to make the biosphere maintenance free because it's difficult to get in and out.  And I've found out nature can take care of itself better than I can.

 

Below is a picture of a glass funnel filling a beaker with dehumidified water.  The beaker overflows and waters the soil.  Soil is sifted in a manner where water moves horizontally to water all plants in the bed.  No mechanical irrigation needed.  See this link on the testing:

 

https://celss.net/tiki-view_blog_post.php?postId=3964

 

Below is a picture of the dehumidifier and the glass funnel.  Glass needs to be used instead of plastics because of the out gassing plastics have.

Inhabitance Habit Control

 

Rodents like to dig and chew on things.  It's important they are placed into an environment where the mechanics of the biosphere are not compromised by the rats.  

First - chewing

They like to chew on wires and plants.  Some to eat and others to make a path for them to walk.  Rabbits do that a lot.  The dehumidifier is placed at the top of the biosphere; out of reach of the rat/mouse.  A long tube channels water to the puddle (beaker) below.  What ever water is splashed out is absorbed by the soil. It's always fresh water.

Second - digging.

Below are pictures of planters that have a screen laying over the top.  Seeds for perennial vegetables are sown under the screen.  The screen will prevent the rat from digging up the plants.  Since the biosphere are so small, every square inch is important.  This is not like an open field.

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Another view.  It is important that the inhabitant have contact with the soil.  Their pee and poop, as small as it may be, is used as compost.  They can't dig up the place. Plants won't have a chance to grow quick enough to feed the rats.