Algae advice needed.....new pool owner

Last week I made plans to open our pool (30,000gal inground). Due to electrical problems, we have been unable to get the pumps started up and the high temperatures here have caused the algae growth to sky-rocket. I now have a concrete swamp pond in my back yard. My electrical problems are being repaired and hope to have the pool equipment up and running by the end of the day or tomorrow.

My question is, what is the best course of action before just chasing the algae. My initial thought was to have the water tested and go from there, but wanted to make sure I'm not missing anything. Should I test the water before starting up the sand filter?

I've been reading tons of great posts on here and have already learned a great deal.
Thanks in advance.