Yellow leaves

hello. It could be unbalanced PH, lack of nutrients or lack of good water quality, genetics or simply bad luck. If I were you, I would try again. Good luck.

Looks like a general lack of nutrition.

in rockwool are no nutrients, tapwater rises pH and die Ca in it knocks out Mg as nutrient. green veins and yellow leave is low magnesium (mg) usually caused by low pH, high Ca or low Mg in the media. yellow tipps is sulfur (S) which also starts in the middleleaves of the plant or Iron (Fe) where the plant starts yellowing from there tipps. Iron usually in soil is always enough there, and if there is not enough taken up by the plant, it indicates an too high pH. you should start giving them low dosed fertilizier and check pH on 6.5.

PH might be off or not enough nutrients, can literally be one of them 2 this early a stage mate

well, that's rockwool, eh? or dwc? You need a full, balanced diet from day 1. A seedling can power itself the first week or more but without a full diet, it's going to trend downhill fast. both nitrogen and magnesium are important to chlorophyl produciton, which is what gives the green color, but i have a feeling it's beyond that, too. you need a proper soilless/hydro fertilizer. Jacks 3-2-1 is a great one. Jacks Part A 5-12-26 with generic calcium nitrate and epsom salt can give a plant all it needs.