| | Re: Lighting question
If I remember correctly, a typical 10 gal comes with an 18" hood (those bulbs are normally 15 watts). So, I'd guess you have 15 watts, or 30 with both hoods. Normally, I'd say that you need the 30 watts, but since you only have Java Fern and the tank is sparsely planted, 15 watts will be fine...the Java Fern will grow VERY slow however.
With 30 watts, you'd really need to add more plants to avoid some serious algae outbreaks.
Something about Java Fern is that sometimes all the leaves will die off when conditions change drastically, but the rhizome will stay alive and will send up new leaves in time. Also, as young plantlets form on older leaves, those older leaves will start to turn brown/black and can be trimmed off (and then re-attach the young plants to the wood or whatever).