Question
I'm sorry, I forgot to add that the substrate is gravel, and do I need some sort of fertilizer?  Sarah

Answer
Hello Sarah! I am sorry, I can't find the original question this one refers to. In general marginals do not need much fertilizer if fish are present. Water Lilies and Lotus to need supplemental feeding to produce the best blooms. Be sure to only use aquatic fertilizer so your fish (if you have any) do not get harmed and you do not get an algae bloom. I hope this answers your question.
Brigitte
www.pondmarket.com