Brown algae (I think)

Question
Hi Karen,

I contacted you roughly two months ago to make sure my new aquarium-- a new venture for me-- was being done properly.  I'm happy to say it's been going well.

I have one comet, two snails, and a bullfrog tadpole, all living in a 20 gallon tank with a whisper filter.  I have smooth brown natural looking gravel, artificial plants, a few smooth stones, and a lava rock.  It's a simple but pretty setup.

I began noticing a brown tinge on the lava rock about two weeks ago.  I then noticed it in places on the plastic plants and on the glass at the back of the tank.  At first I thought it was just residue from the filter needing changing, so I changed it and rinsed the black plastic spongey thing.

A couple days later I saw more of it.  I remembered reading something on your site about "brown algae" but when I tried researching I didn't find a lot, maybe I did not go back far enough.

What I did today was remove all the decorations, spot-cleaned the algae from the glass where I saw it, and used my brand-new gravel vacuum, removing about 1/3 of the tank water.  I added fresh water back in (well water, no chlorine issues there) and rinsed all the items until the algae was gone, using an old toothbrush on the lava rock.

The tank looks really good now but I'm assuming it will recur for awhile.

How often should I clean the tank, when will I know the algae is gone, and am I approaching this right?

Also, my snails sleep a lot which I know is normal but are they any help in regard to this brown algae?  My snails have never bred (I've had them since June) but I'm rather wishing they would, in this case.

I'm hoping to get a friend or two for Mr. Comet (my 5 year old named him).  But I don't want to add anyone in if the algae is an issue.

Thanks so much!
Kristen

Answer
Hi Kristen,
Brown algae is a common occurrence. Sometimes we can't be sure why it appears but it does tend to appear in tanks that have a buildup of nitrates to too high a level. Extra water changes and scrubbing off the brown algae are generally all that's needed in most cases. It seems to occur a lot too in somewhat recent setups due to the system still trying to establish and get things balanced out.

The best way to know how often to clean a fish tank is to go by how high your nitrates get just before your usual water change. Below 20 is the a very important level to aim for. Prolonged exposure to high nitrates can cause growth problems and stress in fish and cause many kinds of algae problems as well. So just try to aim to keep your nitrates below 20 if possible. Goldfish and snails are highly polluting creatures so this is something to keep in mind too.

As far as your snails breeding. Snails often lay eggs frequently but unless you have a male, they may not hatch. If you have mystery snails, they will appreciate if the water level is lowered so they have a space of at least 1-2 inches they can crawl out of the water and unto the glass or aquarium hood. They only lay their eggs above the waterline and lowering the water level a bit may help encourage them to do so. Make sure all holes in the cover hood are extremely well-covered because it is not unusual at all to find your snails on the floor several feet away from your aquarium! They are great escape artists.

~Snails tend to be good algae eaters in most cases. They won't keep a tank spotless though and I don't think they really like to eat brown algae too often.

About getting a friend for Mr. Comet. ;-)
Try to make sure your water quality levels are in good order before deciding to add another goldfish. Try to test your water yourself (ideally) or take a sample to your petstore.
Make sure you get the exact readings and know that your water test results should be-

Ammonia-0 Nitrite-0 Nitrate- 20 or less.
pH is not as important.

If your water tests out good then adding 1 more goldfish should be fine.

Best of luck and I hope this helps!
Karen~