First Grow looking to reassurance/advice on seedlings

[Mañ'O'Green]

Does the RO filter remove iron from the water? If so this could be your problem. People who use tap water rarely ever encounter an iron deficiency because the trace amounts in the water are usually enough. But if your filter is removing the iron it could be the cause of the yellowing, which could be mistaken for nute burn.

@Tmonney Mega Crop and most other base nutrients as well as the starting soil contains enough Iron.

 

[aspeedyboi]

145 EC is not a small amount do you mean 0.145 or 1.45 or 14.5? Take a picture of the meter with the reading.

View attachment 1231785

I believe my meter reads in microsiemens per centimeter. If I'm interpreting your chart correctly I believe yours is in millisiemens so I've been using 0.145 millisiemens per centimeter.

EDIT: To clarify the image is a reading of my runoff.

 

[Mañ'O'Green]

I believe my meter reads in microsiemens per centimeter. If I'm interpreting your chart correctly I believe yours is in millisiemens so I've been using 0.145 millisiemens per centimeter.

EDIT: To clarify the image is a reading of my runoff.

Your meter is capable of displaying the PPM and Temperature in °F it is mode 3. It will eliminate the charts if you could post in the PPMs as well as EC