I think at this point try to scrape as much off as you can and stick to regular water changes. Eventually all the silicates will be removed (which is what diatoms feed on). If you'd like to speed things up, maybe add an oto as a one-man clean-up crew (the RCS will help). There are chemical products but I would look at those as a last resort. Completely up to you! This thread was pretty informative for me when I had a diatom bloom: http://www.aquaticcommunity.com/aqua...ad.php?t=60144
Nice tank, either way
I have a Chi myself! I have an Elite submersible Preset 25-watt mini-heater that keeps my water temps between 68-73 at the lowest setting. It's not super pretty but it works. I could have placed it sideways and behind the filter now that I look at the picture... not sure why I didn't, hah!