I plan to grow one ryder cross. Can I use two 6500k in the seedling stage and than add two 2700k on top shortly after. 50/50 ratio entire grow period. Reason being is I already bought two 6500k and I want to get them some use.
Use all of them in the beginning if you can. You should have around 100w for one plant, mixed spectrum is always a good idea. I recommend you have 2 6500K and 2 2500K for veg, and 4 2500K and 2 6500K for flowering.