It is telling you PPM's. EC is expressed in 0.1 measures and must be converted on dif scales. Some meters will tell you both and give conversions for dif apps.That's 1350 and it is way high for seedling. For small seedling it should be around 300 or 400. Like 1/4 strength. You can just remove some water and add fresh to bring it down.

What kind of water are you using ? Hope it is not the tap water at 701