My tank is cycled and my fish are very healthy. The water levels are perfect and I've been doing weekly water changes but I've recently noticed some brown patches on the stones and glass inside the tank that look like mould or something. Is this mould and is it bad? And if so should I wipe it off? Thanks

Jenny, sounds like brown algae to me. It mostly develops when the lighting on the tank is not strong enough to build green algae. Do you have any light on your tank?
Despite looking not so good, it does not harm the fish in any way. You can clean it up with some algae scraper from the glass, and wipe it off the ornaments. When having sufficient lighting, it will turn into the more desirable green algae. ....

I love my magnetic scraper. It is so easy to use. You might try that if you don't like the looks. I do it every 2-3 weeks for my main tank.

HI Jenny,
Several months ago I had the same brown algae. I hated it, it made everything look yuck. Thank goodness it comes off easy. Now I have Beard algae and that stuff is terrible to scrape off.
Between the brown and beard, I only get a couple days after a water change, tank cleaning that I have a nice bright tank.

I had the gross brown algea too heehee. I leave it on the ornaments, but take it off the glass.

It took about 6 months until the brown algea turned to green? It's still brown on the glass, but on the plants and ornaments it's green. I like the green much better.

The fish like to eat the brown stuff too, so if you don't mind the looks of it, you can just leave it.

Jessica

Thanks guys! I'll get it off the glass but leave it on the ornaments then. I'm glad it doesn't harm my fishies Thanks again.