We put some water plants into the small pond to dress it up a little. There are also some invisible fish in the pond. Given the high death toll of our fish, we assume from being eaten by birds, we got the bright idea of buying fish that the birds won't see ... but nor do we so it seems rather pointless having them.
Romans 1:20 New International Version (NIV)
"For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that people are without excuse."