Like I said, the 'something' is most likely not enough soil/nutrients, usually corresponding to a pot too small.
When you say you constantly have to refill the pots with water, that leads me to believe they were way too small also.
I use half barrel liners and other big pots about the same size.
I top them off once a week, maybe twice if we don't get much rain.
Yes, they are heavy and big, but we use a handtruck to move them around.
Another 'something' that I believe some people do is stunt the growth with too much fertilizer,
especially the type like pond tabs or broken up tree spikes, or tomato spikes.
(and also, when using my recipe, by NOT following directions and using fresh manure instead of composted)
This are NOT slow release fertilizers, and if you use too much, too often, you will stunt, if not kill your lotus.
Too much fertilizer will cause the leaves to look funky, curly, brown, and no blooms.
The roots and tubers get burned by excess fertilizer, and lose the ability to absorb nutrients and/or water.
Root/tuber burn often is so bad, it causes root/tuber rot and then the death of the lotus.
This happens with water lilies too.
(which I also believe in HUGE wide pots for multiple daily blooms all summer)
I use Osmcote and COMPOSTED manure. I do not use any monthly (or weekly, or bi-weekly or tri-weekly) fertilizer after potting them up every spring.
The bigger, wider pot, slow release Osmocote and the compost is sufficient to give the lotus enough nutrients to have multiple daily blooms all summer.
One year I did not repot a couple lotus, they bloomed for about a month and then stopped.
They did not bloom multiple daily blooms either, just sporadically for a month.
This year I did not repot most of them due to the fact I am moving in 2 weeks.
I doubt I will have many blooms this year.