No water changes after adding the safestart. It will bring ammonia down. Test your water fr a couple of days. I wouldnt do any wc for atleast a week unless amonia is rising which it shouldnt
Good advice by coryloach but since your using safestsrt the wc would be counter porductive
A supplemental light may be worth a try for a few hours in the middle of the day when the light through the window is also brightest. If you see any signs of algae, back down the light duration of the artificial light. You can set it on 6hrs a day lets say and see from there.