Bowl Fungud

Question
Dear Brit - I have owned a blue Betta fish for about a year and he's been happy and healthy the whole time, and still is from what I can see.  My problem is, there is some sort of bright green fungus growing on the insides of his bowl and on the stones at the bottom of his bowl.  It's very green and very sticky and hard to clean off.  I almost have to scrape it off every week. It's been growing there every week for about 2 months, usually about 3 days after I clean the bowl is when it starts. There doesn't appear to be any fungus on him, though. I clean his bowl every week religiously and without exception and I use the Betta water conditioner everytime I clean, but that fungus keeps coming back.  I have no idea what is causing it and I'm afraid it's going to eventually make my poor fish sick.   What is it?  And how do I get rid of it?  His bowl is a very hard plastic, so I was thinking maybe that was the cause, although I don't see how.  Would a glass bowl be better?  Should I clean his bowl more often?  I love my fish and I'm determined to keep him from getting sick.  Can you help please?

Answer
Hello Lisa,
That is actually a kind of algae. Algae is not just green, but can actually be blue, brown, and a few colors in between. This just means that your bowl can support life, and is not necessarily a bad thing, as long as you don't let it get out of hand. There is nothing algae can do to harm fish in small amounts.
If your bowl is in bright light or near a window, this is most likely the cause of your algae problem.
A tank should never be placed near a window in any case because the water can heat up much too quickly (and the smaller the tank the quicker it will heat up).
PLastic or glass, the results will be the same.