water doesn't help with cycle tank, "cycle tank" require bacteria to build up in your tank mostly on LR
and sand bed. It is not surprise that you have algae problem with new tank, especially when you got fish in there. It already has high amount of nitrate in the tank and adding extra fish waste and left over won't help also. I would suggest you keep an eye on the water parameter for now, once your tank is cycled, you can start try to find solution to get rid of the algae. As for the fish, I would suggest you return it for store credit. I don't support use live fish to cycle tank and it is adding problem to your algae issue right now.
There is no short cut to cycle a tank and the beauty of the this hobby is "patience" . I have to say this again, stare at a empty tank is boring, but few months down the road, you will be very thankful you took the time to wait. Cuz a tank that didn't fully go thru cycle can end up an unbalance environment and you will fighting with nitrate spike and algae issue night and day.