red lotus growing very slow

i started off with a very bad conditoin red lotus form LFS. i threw everything out except 1 new leaf with roots. how i got 5 leaves (after a month) that are the size of a dime. its running in a smooth planted tank with everything else thriving very well. 4.5wpg, flourite, diy co2. im not adding any ferts for now.

is there another reason why my lotus is growing so small? im going to add some of Jobe Fern stick in the morning.
any other suggestions?

its in an thriving algae free tank. i dont have any test kits and dont want to buy 10 bottles of pure substance and try to create the ultimate potion.

thanks

oh thanks for the info, now ive done some research and saw some pics, i wouldnt midn if they stay small.