Proper wattage?

changing bulbs wont help you. you need more light.like said above you can use t-8 shop light.
i have some 29g tanks now, and my low light has a 65watt bulb on it and is on 7hours a day to keep the algae down.
grass like plants and marimo balls need medium lighting around 2.5wpg to grow.
yes. most likely a simple bulb change wont do. you might get away with basic low light plants though.
 
java fern, java moss, anubias, and maybe crypts.

floaters...anacharis & hornwort should do well. hornwort grows in almost any light.
Najas grass may do Ok too.
I've found cabomba to be a bit fussy and likes medium light.

Most plant sellers specify lo/med/hi light requirements. you're definitely in the "low" category, tho it may look bright to you.

See
http://mikeswetpets.com/Categories.bok?category=Low+Light
 
can anacharis root itself at the bottom?
 
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