trainwreck from seed

growing 5 feminised trainwreck seeds about 5 weeks old got 4 leaf grows [internodes] about 8 inches tall look healthy temp averages 78 to 82 and humidity averages 39 to 45 but may go to 56 through dark period when should i take a cutting of each and when to flower b very grateful for all info as new but enjoy watching the babies grow so keen to look after them

trainwreck from seed on second week of flower cycle temp drops from 76 to 68 in dark period and humidity goes from 45 up to 55 in dark air circulation fine not put filter on yet as no smell yet but look healthy n green feed less than full strength vitalink nutes daily by hand (coco coir)and feed distilled water (ph;d)once weekly to stop any lock up and to freshen plants if theres anything im wrong about will welcome all comments as im a newbie thanks
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