Yes with this being your set up you will have to keep tinkering it till you get the temps up.

"From Costa Rica weather go visit Costa Rica"
Overall, the temperature in January as opposed to July, for example, does not vary greatly. The average annual temperature in Costa Rica is between 70° and 81°


Yes put something over the glass.
A radiant heat panel doesn't dry everything out like the lights do.
The thing with substrate at the bottom looks really thick from the picture its difficult to see because the picture is dark. The under tank heater can not up the ambient temps with the substrate.
The folks that sell that product, tell the customer to put paper down.

How cold will it be in the room over winter?