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Brown Fungus

25 9:11:09

Question
Hi Chris i'm new here but i thought i could get a simple answer for my sometimes confusing problem. It seems that no matter what the fish we have (freshwater) seem to die off after about a month. The tank is about 35Litre has trickle type filter using matrix stones(i think that's what it's called) has two airation stones and plastic plants, with a little gravel. We had up to five fish but then they slowly died off. We have one left (Goldfish)at the moment who had some white spots on him/her and since we moved house i did a water change and gravel clean and he is now looking really good. But now there is a brown fungus that has returned after two three days in little places around that tank. On the side of tank on one of thew air stones and the little treasure chest.
Could you please help me by explaining what this problem could be and how to rectify the problem.
Your help would be much appreciated
Adam..........Sydney Australia

Answer
Hi Adam;

It's just algae and nothing to worry about. It's a type of algae that doesn't need much light and is common in tanks that have been overcrowded, or have just been through a break-in period. It looks weird but all you have to do is wipe it off with an algae pad right before each regular  maintenance water change. Remove 25% of the water and vacuum the gravel every week.

Goldfish are very messy guys. The tank tried to get through the break-in period with so much waste toxin that it killed the fish. There really should only be one goldfish in that size tank permanently anyway. They get to be over 6 inches long and make lots of waste. Here is more about goldfish and their needs;

http://www.firsttankguide.net/goldfish.php

Here are some links to info about new tanks and what happened in your tank;

http://www.xanga.com/Expert_Fish_Help
http://www.firsttankguide.net/cycle.php

At Your Service;
Chris Robbins