The hornwort looks like it needs something.
How much light do you have over the tank....and is it the 5g?
Are you dosing any nutrients/ferts?
Is the hornwort new?
If not, it may be a lack of nutrients. You might try picking up a bottle of regular Flourish. It has alot of nutrients that plants need. Your lighting looks fine for the Hornwort, which would have been my first guess, had I not known your lighting.
From what I can tell, the Java fern looks fine. One thing, if you have the bottom part buried in the substrate, pull it up a bit and just bury the roots (not the hard stem like part).
that hornwort is looking a bit ratty. The reddish tips may be indicative of lack of nitrates <mine turns a bit red when I forget to dose KNO3). Under good light & with enough nitrates (hornwort is a nitrate sponge), it is possible to see it grow an inch or 2 overnight!
Java ferns I find to be very slow growing, and I only see growth over the course of weeks.
I usu. dose weekly with my pwc. Some dose 2-3x a week in low tech tank & daily in high tech ones. You usu. need to experiment a bit to find a right balance for your light level & plants.
There is the EI approach - you dose enough of all nutrients (actually an overdose) during the week, then do a 50% pwc to reset the tank & repeat. <There are schedules on the net if you are interested.>
Personally, I start low & escalate. I start at weekly dosing. If the plants look good, I just carry on. If the plants start to show signs of deficiency, then I increase the dosing. With plants, you have to have patience .... you have to give them a couple weeks for any changes to show results.