Brown stuff in my aquarium!

Question
Hi, 1 month ago I bought 1 Siamese Fighting Fish. The aquarium is 54 liters, (60cmX30cmX30cm) and has 1 pirate ship, 2 rocks, 3 silk plants, gravel, filter and heater that came with aquarium set up, light built into aquarium lid! I feed Percy once a day, I give him all the Sera Bettagram or Tropical Betta food (about a pinch full) he can eat in 5 minutes. I turn the light on in the morning and off in the evening. I have been monitoring the levels in the tank and think that it is near the end of cycling-the levels are Ammonia:0, Nitrite 0.2, Nitrate 2. I was doing a 10% water change daily, and as the levels have been dropping off I have been doing 5% water change daily. He seems to be happy, swimming around, eating well. Much better than the first week he was in the tank when he hid behind the filter and wouldn't eat.

My questions are:

1) I have noticed brown stuff on the plants and walls of the aquarium, it is in circular patches. It is worsening as time goes on. There is also dark colored slimy stuff and brown patches on some of the gravel. It smells stagnant/mouldy when I take the plants out to scrub them. What is this?! Is it dangerous for my fish? How can I get rid of it?

2) I think I will probably leave him in the tank on his own and not get other fish for fear that they will nip his fins or eat him or he will fight them. Will he be lonely or do Bettas prefer an individual set up? If I was to get some other tank companions which would you recommend?

Thank you for your help,
Felicity

Answer
Hi Felicity,
I have had Bettas that didn't mind other tankmates and I have also had a few that prefered to be by themselves. The ones that I have now have their own tanks and seem to like that alot better than having other fish around them.  If your do decide to try other fish with them be sure to not get any fin nippers since many times this happens no matter how  selective you are about the fish you place with them. You take a chance with any fish since the Betta has such beautiful long fins and it is tempting to any fish. You could try Cherry Barbs or Rasboras if you want to see if it will work out with adding fish. There is also the chance that Percy has already decided that it is his tank and could be really ready to fight any fish that you place in his territory.
As for the brown stuff appearing in your tank. Most likely it is brown algae. There are various theories on why this appears in both new tanks and well established tanks. When I have had this happen I have increased water changes and eventually it disappeared and was replaced by green algae. I am sending you a website that explains the different algae, including brown algae, and why it occurs and ways to try to get rid of it. It shouldn't harm your fish but it does make things look a little ugly until it is gone. Here is the website:
http://www.thetropicaltank.co.uk/algae.htm
Best of luck!
Hope this helps,
Karen