Everything I plant in my concrete water fountain dies, WHY?

Concrete sucks up water. Maybe you need to seal the surface?

Are you watering it frequently enough? Sometimes plants in a container will dry out much quicker due to the shallow container not being able to retain much water. Check your soil frequently to make sure it is staying moist enough. Also....it maybe too shallow for the type f plants you are planting? Some plants need deeper soil for the roots to have room to spread and grow properly. Just a thought.

I had a very shallow fountain that no longer was used as a fountain. I turned it into a planter. Since it was very shallow, I sprinkled some very small stones for drainage and planted sedums and various succulents because (a) they don't require a lot of water and (b) they have shallow roots. I didn't drill any holes in my fountain's basin in case I changed my mind some day and wanted to use it again as a fountain. The sedums worked perfectly in the very shallow basin.

I had the same problem with my concrete planters until I realized that the concrete was getting so hot in summer sun, it was "cooking " everything I planted . I switched to succulents and cactus . No more issues .

Use the pot in the pot method.Plant in a plastic pot shuitable for the concrete planter and just place inside.

My guess is the same as C. D. Scallan's - see it all the time with the folks who want ultra modern / industrial type surroundings.