We added lettuce to the empty cups and they caught up to the basil quickly.
WOW!!! the lettuce is looking great for only 5 days. It has already caught up to our biggest basil plant. Im glad we chose lettuce because of the quick growth rate. It seems to do well in a water culture system. We added more nutrient solution and checked our ph. It is around 4 with is not good. We added some ph booster and got it to around 7. This should help them maintain their growth.