Adding clones on week three? Hydroponics?

both in vege? it's old enough? the same formula is fine. There's not really at ime a plantn all of a sudden needs 1 thing. you should be providing it at all times - a well-balanced diet. sometimes you need a shift in flower with a bit less N.. maybe 10-15% less depending on how heavily you fed it in vege. think about humans.. one day a year do they need a spike in calcium? no, that's crazy. The body needs a certain amount of everything, every day. plants are even simpler. also assuming 'clones' means rooted cuttings and not 'cuttings' with no roots. A vege plant is a vege plant is a rose is a rose.

With clones, I typically use clonex by grow technology. It works amazing and dynamo microbials and that's it in the beginning. After about a week or so after transplant, I go to about 1/5 of tip of my normal vegetative nutrients.

Clones should be fine with your "seedling" mix.