TNC Plugs give a steady and continuous supply of plant food directly to the roots of aquarium plants. They are simply pushed into the aquarium substrate where they slowly release essential nutrients over a period of 6 months or more. Nutrient supplied directly to the roots. Will not cause algae Can be used in conjunction with TNC Complete or TNClite Enriches inert substrates - Playsand/Gravel Re-vitalises depleted substrates Economical and cost effective Feeds aquarium plants for 6 months or more Easy to use Supplied - 2 x 10 capsules USE:- Push TNC Plug approx. 4cm under substrate. Use 1 - 3 per plant - Depending on plant growth, planting density etc.