Jul 8, 2020 Thread starter #1 hlbaranwal New Member Member Messages 1 Reaction score 0 Hi all, I have a small lotus pond with mollies. Can I add NPK (nitrogen, phosphorus, and potassium) 19-19-19 in it? Or will it hurt my fishes? If not, is there any fertilizer which can be used for lotus and is safe for fishes? Here is my pond. Thank you.