There isn't enough info here to give you any kind of meaningful answer. I suggest you read the stickies in the fertilizer section and try and absorb a lot of that info. I'm trying to say this as unoffensive as possible (not my strong suit), but this looks like a question from someone that's brand new here and you have over 400 posts.
Your plants need light, CO2, nitrates, phosphorous, potassium and an assortment of trace elements and iron. (The trace elements typically come mixed and are dose together) Plants will only grow to the level of the least available of these. You have to provide all of them at acceptable levels.
In order for someone to give you a meaningful and accurate answer they are going to need more info like; How much light, tank depth, general types of plants, how heavily planted, substrate, water parameters, livestock, frequency and amount of water changes, how many root tabs, how often.
Your plants need light, CO2, nitrates, phosphorous, potassium and an assortment of trace elements and iron. (The trace elements typically come mixed and are dose together) Plants will only grow to the level of the least available of these. You have to provide all of them at acceptable levels.
In order for someone to give you a meaningful and accurate answer they are going to need more info like; How much light, tank depth, general types of plants, how heavily planted, substrate, water parameters, livestock, frequency and amount of water changes, how many root tabs, how often.