Looks like its going to fall

Can you remove the stand on the bottom tier? It just seems out of proportion. You could fashion a bottom out of a plastic trough from tractor supply and position the cement sections around it. Maybe cut the above mentioned base down.

Do you suppose that you might have a collection of three (or four) separate fountains or more likely bird baths that were supposed to be placed in some kind of grouping? Re fountains: are or is there a hole for tubing to get water to the top, and from where? From here it looks like bird baths.

They have the hole all the way through, I think we need a level concrete base grout the bottom side pieces so that the water stays inside the bottom part do you think I have to prime the fountain or seal it?

We have had a fountain like that at church and the large basin at the bottom was the catch pool for the water that was pumped up thru a tube to the top and it overflowed each basin until it emptied into the basin at the bottom and then recycled from there. Each piece has a lip that holds the pieces together. The pump was in a cement housing that was part of the base of the first tier. The bottom basin must be able to hold water without leaking. See this web site for a guide on how they are put together. http://www.davidspatio.com/catalog2/TieredFountainAssembly.pdf

The little in pond, and in your case, bowl, don't need priming but they do need enough water so they don't run dry. They are designed to have everything run OK underwater. I guess the pump would sit inside the bottom pedestal, so the new bottom bowl will need to be big and deep enough to keep the little pump submerged. Fortunately, some of those little pumps are only a couple inches high.

The pumps are small but it will take a larger pump to push the water up 4 feet or so. Measure how high the water will have to go and compare to the specs on the pump. They took the church fountain apart because there was no one to maintain it on an ongoing basis--the evaporation was a lot during the summer and it would get green if bleach wasn't added. No one wanted the every few days monitoring and adjusting. I remember that leveling it was difficult when they set it up. It was in a little prayer garden and was a wonderful addition.

veronica,

If you read the posted instructions for the fountain that looks exactly like the one you have, it doesn't look like you need anything else. The pieces you have around the fountain, those pieces are ornamental only, not a base to hold water.

In other words, the fountain is complete the way you have it. You have to level it on cement blocks instead of the lawn. Then after the fountain is up and running, please read those instructions, you could buy some garden soil and plant plants all around the base of it, that is what those pieces are for that circle the fountain.