Windelov Java Fern getting brown dead spots all over

[Kimlafeiet]

I purchased a windelov java fern from petsmart about 10 days ago, the kind in the tube. I attached it to a piece of driftwood in my 55g rainbow tank. I currently have a standard T8 ballast light with a bulb specifically for plants in it. Dosing API leaf zone and liquid co2.
The fern has lots of dead brown spots all over the leaves. I know this plant was grown not fully in water, so is this normal? Is this die-off of the leaves before new leaves grow, or am I doing something wrong for this little guy? I have 2 amazon swords and an anubias, and they are all great. Seeing a new leaf on the anubias, and the swords have sprouted tons of new leaves and grown several inches.
Anything I can do for this plant or just give it some time?

 

[Mrs.h2012]

I bought a java fern from petsmart, also in the tube as well. Mine has brown beard algae on it. Mine didn't grow at all for a while and got the brown spots as well. I just recently got some seachem liquid ferts that seem to have helped it. Before I was only dosing the seachem NPK pack and API liquid co2. I recently just ordered the seachem fundamental pack (includes iron, flourish and excel) and seachem trace. I'm slowly starting to see some improvement and growth on the java fern. That could be what you need!