Seachem's Flourish Tabs

Ok, so they are talking about the radius around the food tablets themselves. The bulb says its an Aqua Glo 20W T8, does that help? Thanks.
 
Yes, you need more light. A 20w bulb, regardless of type, simply isn't enough light for a 30g tank for any kind of plants. You would want to double the amount of lighting by introducing another 20w bulb if possible.
 
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