You have nothing to be scared of. I dont think I have seen a new tank not go through this process. You can clean the glass and vaccum the sandbed and tomorrow it will be back. The benaficial bacteria that lives in the rock and sand is growing and when it stablizes it will be able to consume the diatoms faster than it appears and problem solved. You might want to consider adding a little more rock also. 1 to 1.5 pounds per gallon is the general rule of thumb. The rock and sand is the biggest part of your filtration. Now I got a bunch of questions for you. Is the hob filter the only form of circulation? What kind of media is in it? What kind of lights do you have? Do you have a test kit? If so what kind? What are the water parameters, and source of water? What are your plans for this tank? That should get us started..lol. By the way I have a 10 also. Been running over 2 years now. Very rewarding and demanding at the same time. Big changes happen fast in such a small volume of water so be patient and go slow.