I can think of four major factors likely contributing to the disappointing squash yield:
1) planted too close together to get adequate light, which also caused them to divert a lot of resources away from fruit production toward capturing more light;
2) lack of proper nutrition (new aquaponics systems take 6-18 months to build up the diverse and rich supplies of nutrients that heavily fruiting vegetables require; coupling those deficiencies with excess nitrogen results in lots of vegetative growth and little fruiting);
3) pH higher than what squash plants prefer (plants have trouble absorbing nutrients if pH is too high)
4) poor pollination (bees haven't really discovered the garden yet)
I'll address these factors and hopefully have better luck with the next round of squash in the grow bed.
Now for some pics. First, from the doorway:
Their vacated section (note the whispy pepper plants on the left):
Into the recycle bin, a.k.a. the fish tank:
It's tough to see, but the junction with the dense cluster has 6 cucumbers. I thought it was amazing when the cucumbers were launching a fruit at every junction (about 3 inches apart); words fail me if they start launching 6 per junction.
This Royal Burgandy bean is about 6" long:
