The wall was a few millimeters to wide, so it did not fit in the tank area.  It was frustrating, but two days later, with a bit of trimming, the wall slid into place. The purpose of the stem wall is for insulation plus a platform to stand on while tending to the plants.  There are two removable lids allowing access to the fish tank and plumbing. Below are pictures of the installed wall and under construction platforms over fish tank.  There will be insulation and plywood on the inside of the tank walls.

I visit the computer lab weekly to have questions answered along with guidance through the wordpress.   My paper has taught me the skill to copy and paste, a skill I did not have, which has made the edit process on my paper less stressful. The group tutorial on Zotero was helpful, but I need to schedule a private tutorial to complete my bibliography.