As expected, these few critters were not able to keep up with the algae growth. I would not go so far as to say it was a mess, but it did look less than attractive. The rocks were relatively clean, and the sand was not that bad. But there was a greenish brown film over all of the glass. Looking through this film made the entire tank look filthy. I tried to get in there with a strong (water resistant) paper towel, but no luck. The film was just too tough for it to handle. Typically this type of film would be removed with a razor blade, but since much of this tank glass is curved, that would be a difficult task.
I recently read about the use of a relatively new cleaning product, the Mr. Clean Magic Eraser, being used on acrylic tanks. Razors can also not be used on acrylic tanks, as they are easily scratched. The magic eraser is, for lack of a better term, a microfiber spounge. The reviews of this product by acrylic tank owners was overwhelmingly positive, so I decided to give it a try on my curved front glass tank. I first did a little independent research just to check on the composition of this sponge, just to make sure that it would release no harmful chemicals in the tank. I decided that the “original” version of this product is the one I must use, as subsequent “extra strength” types which include some type of cleaning agent have also been introduced into the product line, as well as lemon scented, etc.
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So now that I can see that all inhabitants have survived my temporary abandonment, I can safely assume that the tank is stable and it is safe to do a 2 gallon water change and add some new life.