Drop clothes on tanks Yes/NO?

I can not see any problem covering your tank with a drop cloth as a general rule. The only issues may be knocking equipment around when putting it on or taking it off.
 
There should be no problem using a drop cloth as long as you don't cover any of the vent holes in your light strip. I would hold off on doing that just because you are in an almost ideal situation to set up a natural planted tank using the techniques made popular by Diana Walstad in her book. The essence of it is that you use a dirt or potting soil bottom layer covered with coarse sand or gravel to keep it from floating around the tank. Then you plant as many fast growing plants as you can stuff into the tank and give it at least 2 WPG of lighting and / or natural daylight for 12 hours a day. The end result is usually a fast growing jungle that is a stable and healthy environment for your fish. No need to cycle the tank if you give the plants a couple of weeks head start, and the fish food and waste becomes the fertilizer for the tank. I have a couple of NPTs going right now and they are definitely jungles of plant matter. The tank gets a water change every 4 months or so to replenish the minerals that the plants have pulled out of the water column, not because there is anything wrong with the water from the fish's perspective.
I can't bring myself to follow her method completely so I do have a sponge filter in the tank instead of just a power head.
 
I'd let it play out and if you get algae, throw some snails or something in however I know that's frowned on and I'm not exactly an expert. However if you do put a dropcloth over your tank watch where it's positioned, it can wick some serious water onto the floor, I know that much.
 
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