T.A. Oligo Spectrum is a complete mix of micro-nutrients in chelated form and a vital food supplement, approved for organic farming. It is also suitable for spraying indoor plants. For best results, keep the pH between 5.5 and 6.5 and GHE fertilizers are highly concentrated. In order to avoid precipitation, the components should never be mixed directly with each other, but should be added to the water separately. The dosage indications on the bottle are for hydroponics and substrate cultivation, all substrates: expanded clay, rock wool, perlite, coconut fibre, etc.