my white widow is way behind in terms of growing than my critical purple. help?

I answered on another one with this same info growmie. But here ya go again, Cheers! I see a couple possible issues my friend. 1.) Nutrient Lockout 2.) Available nutrients 3.) Overwatering 4.) Light Intensity Again possibilities. Here's why; 1.) At too high of watering ph the plant won't uptake the right range of nutrients. This leads to the plants using stored energy in the lowest growth first. 2.) Some promixes only retain nutrients for up to two irrigation prior to needing supplement. If nutrients are added when they are not needed you risk toxicity issues and could really stunt growth. Some nutrient burn signs may start showing up, but I don't think that is what is completely happening here. 3.) Waterings are the hardest thing to nail because too much you risk suffocation of roots, drowning, or rot issues. Underwatering will cause almost the same signs and damage the only difference is feel. One will be way dried out obviously. Both will show signs if wilting too so pay attention to your medium and try to make sure that the mediums surface dries out between waterings. 4.) Light intensity being too high will keep your plants shorter and you could look at I as the little plants may cower away from the biggest light. Make sure to not destroy them with too much light as a young plant. They only have small leaves and can't really do too much until about mid week 2 of veg. Regardless the plants are suffering as you noticed, but they aren't a lost cause my friend. Adjust your PH you water in at, dechlorinate your water by letting it set out for 24 hours to gas out the chlorine. That alone should help a lot.

Over watering and soil without enough drainage-i.e perlite/vermiculite. it will come back if you ease up on the watering...as in wait a day or two longer than you are now before watering and use less each time for a while too. But next time add some extra perlite-around 30% will do, and then be careful not to over water.

I didn't see a diary. How long have the sprouts been above ground? What is the pH of the soil and the water? I assume you are NOT fertilizing. My first thought is too much water. I have no experience with that soil but most store grades of potting soil are too heavy. They are optimized for tomatoes and flowers in a pot sitting outside in the hot sun. They hold moisture a bit too well for an indoor grow unless you are careful. I use Fox Farm Ocean Forest which I mix 3 parts soil with 1 part pearlite to make it even more light, airy and free draining. With seeds & sprouts you have to approach watering a bit differently. Keep in mind that most of the plant is below ground. If you see a sprout 1" (2.5cm) above the surface it's roots are probable 3-4" (8-10cm) deep and that is where the problem can occur. Because the plant is too small to take up much water almost all the water leaves the soil through evaporation. I like to water beyond where I think the roots will be. Then for a sprout like yours I stick my finger deep (at least 2nd knuckle) into the soil to check the moisture. At 2 knuckles deep I want the soil to be just slightly damp or dry before I water again. This is in contrast to a larger plant it is taking in a lot of moisture through the roots. In that case dry one knuckle deep can be a sign to water.