Marcel, what's the usual "rule" on size and developing floaters vs light intensity and fertz ?
Any tips on getting them to develop floating leaves?
Hard to say in lumens or par regarding light.. I'm growing 2 differnt sp. at the moment in aqaurium.
Still growing this one
https://www.ukaps.org/forum/threads/i-think-i-am-in-love.37099/
Back then it had a fair amont of light with calculated (not measured) over 4000 lumens LED and added CO², water column ferts and a clay cone under the bulb every 2 months. Today this very same tank has no light at all other than inderect light from an east facing window and no more co² nor ferts for over 2 years maybe. Note the size difference floating as well the submersed growth at the substrate i guess the lilyball outlet is a nice reference. Same lily 5 times smaller. growing both forms, floating and submersed.
They are darn addaptable.
In a way it also is very sp. depended. The other one in the Skylight lit tank. Only makes floaters in the summer with sufficient day light hitting the tank.
Pic taken 14 juli lately. Only growing floaters - with artifical light switched off
Pic taken today, november, slowly shedding it's floaters not growing new ones and only growing submersed form leaves. - Whit artificial light switched on. Make a best guess..
Must be light deficiency for this one.
This are both tuber lilies that could do outdoor and survive a winter. But still both have different requirments.
Than Tropical sp. such as N. zenkeri, N. nouchalli/stellata and cross hybrids from it or the N. glandulifera etc. are ext to this more temperatur sensitive. Ask
@Edvet he can confirm how difficult these tropical buggers can be. Glandulifera alledgedly hates anything bellow 28°C. I failed misserably with it 2 x.
Other consideration is flow, 10 x turnover is likely to much for it to develop floaters. Going with a minimal possible flow is best..
That makes it rather difficult to give an conclusive answer on rules on the entire genus.. It can be either this or that or multiple at the same time.
"Not enough light", "to much flow" or "fert" and or even "temperatur" deficiency.
With in this genus the specific rules should be somewhere with in these 4 factors.
With the temporate small bulb varieties listed above you have the best changes finding the correct combination in a relative average range. As said with the tropical sp. it might not be feasible in your setup to go + 28°C for a longer periode to see if it improves.
