regarding magnetic cleaner

My 2 cents view...

Magnetic cleaner - effective for softer algae, cause turbulance when cleaning, corner cleaning not possible.

Algae scraper - may cause scratches in not careful, rusty, very difficult to clean blind area (esp. those braced tank), dry but tired hands.

Credit card - Free, cleans hard algae very well, can reach corners limited to your hand's length, wet hands.

Scouring pad - (never use bf but, no no for me) likely to leaves tiny scratches and you never know wat chemical is in it (maybe some anti fungi agent) which in turn will be released into your tanks...yike!

I am also using the bakers cutter (plastic dough cutter), why, for big area target where credit card is too slow, it seem sharper too maybe due to the knife like edge.