not sure what this is. It bloomed after a big water change. The tank has been up 8+ weeks and this came out over the weekend. The rock was curing for 13 weeks, started with a 2 week cycle of bleach solution then 11 weeks with just salt water changing the water weekly. Please help.
That some yellow stuff! I’m guessing diatoms if it blows off easily and possibly chrysophytes if it’s more globular. Either way I wouldn’t worry now as the tank is maturing.