This alright for general plants in tank...
http/cgi.ebay.co.uk/SERA-sera-florena-aquarium-plant-fertiliser-50ml-/250749337945?pt=UK_Pet_Supplies_Fish&hash=item3a61d34159#ht_1381wt_905
Chris
You can use it , but if you dont have loads of plants in you tank then root tabs are a good idea. They come in tablet form and you just plant them in the substrate next to the plant for a slow fert release over a period of between 1 and 3 months.