The topping will have slowed growth down,the plant will have been putting all its effort into the topped section of the plant,
I think that the pot the plant is in is fine for the time been,let it get really root bound before re potting this will make the plant,
shoot up a lot faster than normal when you do re pot.
Other than that looking fine,perhaps a little small but its all about the amount of light there getting,my plant's are around 1 1/2 ft tall from a t-5 x 4 tube one that is around 3 ft long,t-5 lights are under rated,i do all my vegging under t-5's i only use my 600 h-p-s lights for flowering,and they love the t-5 room.
This has never effected my yeild,i all ways can tell you what im going to get from each plant just through the past grows that i have done,I put some pictures up of a t5 vegged plant tonight,its been in that room 5 week and i have topped every single top on the plant more than once its about 18",and is perfect, ready to flower.
I used to do all my vegging under 600 h-p-s lights,but i took some clones from a plant i had just flipped,they went straight under the t-5 and i left them under the t-5,i was suprised just how good they looked so after that i have all ways stuck to veg under t-5 and flower under h-p-s,it has saved me a fortune on electric over the time i have been doing this stuff.
I build custom built vegging unit's now for friends and friend of friends ext,every single one of them can not understand why they used to use h-p-s lights to veg some even flower,under them but this i would not do my self,the few that do,do strains like auto's and do get good weights from them,but i do add 3 extra flouresent tubes,to the units warm day light spec,these seem to be more orange redish in coulour so they help during the flowering,
Also a bit early to be giving ya advice on this stage but don't super crop,get a table over them or just tie them down,super cropping ,doe's not mean you are gonna get a super sized yeild
if any thing i think it effect's the yeild in a bad way less not more,lst is the way to go,think of it like drinking through a straw that has been bent,its is harder to up take liquid's.
good luck
hope this helps tyke
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