First grow

D03872 Edit: I want to thank everyone for their reactions! Although it doesn't seem like there's a clear consensus yet, I feel more informed to make decisions (or leave things as is) for now. I'll try to keep this diary up to date. Hi everyone, this is my first grow. If anyone has any specific questions, I have lots of pictures and information if someone needs it. The plant stays outside for 10 hours a day and I supplement some light with a simple, screw-in LED growlight with some red/blues. I made this diary to ask a question: I started my seedling indoors, but I moved it outside because the weather is very nice, clear blue skies. The leaves have started to get a lighter color, from a deep green to more of a lime-green. Can anyone explain/see if something is going wrong here? -- I'm using a mix of Spa water (ph 6.0) and tap water (around 7.5-8 according to local water company). I don't have any equipment to measure exact water values, so EC and pH are just guess work unfortunately (I spent everything I want to spend already, for now at least). Since germination I've watered on day 1 and day 2, approximately 100mLs each time. Because the soil seemed a bit wet I've stopped watering for a bit, only did 1/2 sprays down the stem each day (so max a couple of mLs). Currently, the top inch of the soil is dry. In doubt between watering today or tomorrow, I don't want to overwater. I did not water my soil at the beginning, it is a seedling soil with low amounts of nutrients, I also mixed in 15% perlite. I added a "slow release nutrient" mix (on the lower side of recommendation) to the lower two-thirds of the soil, it's what I had to work with. -- May 30th update: changed the watering to a 60/40 mix of tap water (pH 7.8 avg) and spa (ph 6.0), so this should lead to a pH bump, let's see what this will do. I noticed that my soil bag says that the pH is 5.2-6.2, which would mean that the soil is slightly acidic, meaning the yellowing could have been some form of nutrient deficiency. Time will tell. I do get the feeling that she should've grown a bit more in the last 2 days.

D03872 The yellowing/lime green color is still occurring, with also some green veins starting to show in the centre of the plant. Yellowing seems to originate from the new growth and from the inside out, between the veins. Growth seems very slow and I would have expected more growth, but it is still occurring (visible in second set of true leaves). -- Added day 12 picture. Yellowing seems to have slightly decreased, am now absolutely sure of pH of water between 6 and 7 (around 6.4-6.7). Plant still seems a bit stunted, growing inside now due to rainy weather.

D03872 Week 3 now, it's very clear that the little seedling has stunted growth (although she does still grow). I've started watering a bit more (150mL every two days) and she's inside now under a 10W LED grow light. It's become clear to me that during the first two weeks she was a bit underwatered (+ probably wrong pH water).