Rotting?

[dewbrew]

I've been trying to grow these lotus in a tank, however it seems that many of the leaves rot a while after opening. Have had many leaves and all of them rotted, maybe it's because the roots are still adjusting? I repotted them recently to use better soil/mud and added fertilizer. Also, I live in a country where the summer is very hot and can reach 40° easily. Should I cover them from direct sunlight (they get around 5hrs of direct sun a day)?
Info:
Using tap water as we don't have much rain water, but can use distilled water.
Two lotuses in 4 inch of mud and aprox 10L tank.
A couple of snails in the tank, I try to get rid of as many as I can.

 

[dewbrew]

Also, there is a water pump that passes water through an aquarium filter (can be seen in img- blue pipe and lunchbox)

 

[Hound Heaven]

I can hear how much they mean to you, me too. I've read that they should not be fertilized until 2 or 3 leaves have become airborne. Mine get about 7 hours of sun a day, planted in clay, unscented cat litter about a foot of circulating pond water above the roots. Several leaves are now above water and I'm anxiously waiting for a bud or two. I moved them (carefully!) from a deeper tub over the winter, time will tell if I did it right.
Several here grow them successfully, seemingly effortlessly, so they will likely have plenty of good advice for you.

 

[j.w]

@dewbrew

 

[mrsclem]

As @Hound Heaven said, no fertilizer until you get several leaves above the water.

 

[dewbrew]

I see, I tought so but I posted on facebook and this woman insisted i should fertilize them. They're the stuff you put in the soil like beads, I'll see if I can remove them still.

 

[mrsclem]

You can't believeara everything you see on facebook! I've been growing lotus from seeds for years and learned the hard way when I killed off over 20 seedlings by fertilizing too soon.

 

[dewbrew]

They are doing great now! Areal leaves are shooting up by the day <3 Thanks to everyone for the advice!