Hey, about container size. When everyone says a 5 gallon pot, is this a 5 gallon BUCKET, or a 5 gallon nursery container? That's quite a big difference! If I veg clones for 3 or 4 weeks AFTER rooting, can I use a 3 gallon container to veg to around 12 - 18", then transplant to 5 gallon NURSERY...