Normally, when a pool turns completely green from algae, it has been neglected for several weeks or more. There are usually leaves and other debris piled up in it, and the pool flipped because the pool became eutrophied. Eutrophication is when algae takes over a pool when its growth/reproduction rate exceeds the killing rate of the sanitizer (chlorine). You can kill algae with chlorine and algaecide all you want, but if you do not address the micronutrients that fuel the growth and reproduction rate, the pool will flip back to green once again. Chlorine does not remove micronutrients like phosphates.
The Orenda Green Pool Cleanup procedure is the most efficient way we know of to not only clear a green pool, but to help prevent it from flipping back to green. And there are no specialty algaecides needed! Chlorine itself is the best algaecide. Our cleanup procedure is a 1-2 punch of non-stabilized chlorine to kill, and Orenda chemicals to clear out the waste left behind. Orenda products are not algaecides and do not kill anything; chlorine does.
Step-by-step procedure:
https://procedures.orendatech.com/gre...
Articles about algae and why phosphate removal helps:
https://blog.orendatech.com/phosphate...
https://blog.orendatech.com/understan...
https://blog.orendatech.com/algae-no-...
https://blog.orendatech.com/phosphate...