The lines aren't nearly as visible in real life, the flash makes them stand out. What that is are custom plastic sheets set in runners. Rather than scrubbing the coralline off the background, we have two sets of backdrops that fit in four sections. While one set is in the tank, the other has been washed with hydrochloric acid and is waiting to be swapped in. The two reef tanks are identical, so we really only need three sets of backgrounds...two in use and one cleaned and waiting to go.Nice tank. What are those vertical lines in the blue background?
We can't let coralline grow all over everything like you can in a home aquarium - the public just doesn't understand, and thinks it looks "dirty". Before I had these built, I watched one of my aquarists spend 45 minutes cleaning about one square foot of the tank's epoxy back with with a TOOTHBRUSH! There is no way I could let that go on..... $700 per set for these.
Jay