I'm assuming you've germinated Nelumbo nucifera, the pink/red one. They are a bit variable in colour but can also come out with some white. Going from seed you'll need to wait til they flower to find out.

My method for keeping mozzies out is to plant Utricularia gibba. They're carnivorous plants and being one of the floating species they do a good job of swallowing up any newly hatched mosquito larvae. I've had them in water containers for years and have yet to see any larvae in with them.

I use heavy clay soil and mix slow release fertiliser in with it. In ponds I use monsoon tablets (Bunnings have them). I don't have access to cow manure but probably best not to over do it if it hasn't been well aged.

They produce a lot of roots and runners so won't stay in pots and will be all over the bottom of the aquariums. For that reason it's usually better to put them in their permanent position as early as possible. I put a small one I germinated over winter into a 4 metre by 2.5 metre pond just less than 2 months ago. Already it's sent runners throughout most of the pond and has sent up over 10 aerial leaves. (It was fed with monsoon tablets.) The rate of leaf production is accelerating, within the next few months I'm expecting the pond to be tightly packed with leaves.

tropic ...you must like the flowers that I do. Anyway...thanks for your advice. I will get the Monsoon tablets from Bunnings tomorrow. Would Bunnings have Utricularia gibba?

They're unlikely to deliberately have it but you'll often see it in with other water plants in nurseries. It's fairly common in wetlands and in botanic gardens. If you've any contacts in Carnivorous Plant groups some one there would have it.