distance and power for lights on seedlings

I use an app called Photone and I bought a clip on light defuser for my phone and it seems to work well. I set my seedlings at 250 ppfd and they’ve done really well, I think I always used to give too little light and they would grow leggy

Go buy your lights instructions they mainly state between 30-50cm above plant canpoy its not really a question of light really its a question of heat you could have the light 3mm above the plant if you wanted though this would most likely bleach the plant white. i would always recommend around 30 cm from the top of the seedling depending on the light if its led yeah about 30cm you don't want it too far cause the seedling will stretch up to the light but too close and the heat from the light could burn it and you could bleach the plant. the power is completely up to you along as the heat is as far enough away from the plant and you have good air extraction (negative pressure) you will have no problem running the light on full power which is what I do with all my seedlings though the plants don't need this much light at this stage and I cant say it speeds anything up but its just what I do lol. many other growers will say around 50% of the light at this stage would be sufficient but along as its at the right distance it don't really matter it is very important to have your light at the correct distance all the way through the grow as if you don't your internode spacing with stretch and you will get less branches on your plant but keeping it low and at correct distance you can get your internod spacing to centremeters rather than inches and more branches means more bud :)

Veo en su diario que tiene un sp3000. Las especificaciones dicen que a 30cm al 100% de potencia ofrece 1200 ppfd. Para sus plantulas puedo recomendar: si necesitamos 300 ppfd pondría la lampara a 60cm al 60%. Estaríamos obteniendo 310 ppfd. Esto es para plantula. En etapa de vegetación la planta necesita 600 ppfd y a 60cm seria al 100%. En floracion como dice el manual a 30cm al 100%.

i find the first day or so they don't want much but they quickly demand more, if you want to avoid needless stretching. no matter what you read, allow the plant to dictate your adjustments. too much stretch = needs more. no vertical growth = needs less. take some notes. it'll be similar next time and you don't have to guess. a lot of variables are at play that make one garden have different needs than another relative to anyn stage of life cycle. let the internode length guide you in this endeavour :P

Please see below link to the free LUX App Android - LUX https://play.google.com/store/apps/details?id=com.doggoapps.luxlight&hl=en_GB&gl=US&pli=1 Iphone - LUX https://apps.apple.com/us/app/lux-light-meter-pro/id1292598866

It’s very hard to judge this because every light is different. Take for instance, I have a 250 Watt light and another 700 watt light. If I put my 250 watt light 18 inches above and turn it to 30% the light is going to be much less then the 700 watt light turned to 30%. It’s best to download a PPFD App and measure your light at the top of your plant. For seedlings, a PPFD around 300 is great at 18 hrs on and 6 hours off. If you do not have the ability to download a PPFD app, the manufacture has suggest recommendations for the light in which they tested all the PPFD levels for the various stages of your plants growth. I hope this helps.

I don't rely on distance and power alone. Instead, I maintain the light at a consistent distance of 30-40cm from the plant and adjust the power according to the Lux value. You can easily monitor Lux values using a free app called Lux. Please see below my guide for LUX LED Light - LUX Clone and seedling stage: 4,000–9,000 lux Vegetative stage: 10,000–39,000 lux Flowering stage: 40,000–65,000 lux