Algae? Fungus?

[kaliya]

Hi,

I am new to the forums, and would still call myself a newbie at aquariums.

I have had a 29 gallon freshwater tank for about 5 years. Where I live before I had no major algae issues. The tank got green algae but it was just a minor cleaning nuisance.

I moved in July. I brought along the same gravel (well cleaned) and my live plants. The fish I didn't, I took them to a local pet shop rather than kill them. Two days after moving I set my tank back up, using the gravel and the plants from before. I let it cycle for 2 weeks, tested, everything was acceptable. Went and bought 3 black skirt tetras as my testers. Two weeks later they were fine, so I added 2 cory catfish, 1 rubbernose pleco, and 3 more tetras. Two or 3 weeks after that I did my first cleaning. It wasn't very dirty, didn't do more than 15-20% water change.
I had issues getting correct water temperature to replace the water. For some reason cold water was more warm than cold, so the replacement water was a couple of degrees warmer than I liked. Within 2 days one of my cory cats died. I figured it was due to the water temperature. Faster forward to next cleaning, same issue with water temperature, but don't think that was an issue. One day after that cleaning I notice white stuff on the gravel. It spread pretty quick and next thing I know my other cory and pleco are dead. The tetras were just fine. I clean the tank and had to agitate the gravel just to get the stuff off.

Needless to say, it came back. I pulled the gravel out, cleaned it by hand, cleaned the filter, and everything else. I replaced as little of the water as possible since knew was risking a lot with that much cleaning. The tetras were troopers tho and made it thru it all. It looked good, didn't see any signs of any growth coming back, so I added 2 cory cats again, as I needed bottom feeders to clean. Week after, I did a small cleaning again. And the next day or so the stuff showed up in the gravel again. I've tried fungus treatment. No luck. I could replace the gravel, but I'd prefer to find the solution before replace stuff just to have it return. Anyone have any ideas for this?

 

[Fresh2o]

This looks like fungus that grows on uneaten food. How often and how much were they being fed?
Setting up the tank and letting it cycle for two weeks is not cycling at all. You should read up on cycling and the nitrogen cycle. Actually, changing MORE water and cleaning the tank LESS would be better for it.
I'm guessing that the fish succumbed to ammonia poisoning. You ought to test for ammonia, nitrite, and nitrate. Or get the pet store to test these for you (if they do, request real numbers rather than an interpretation "It's fine").
At this point I can only recommend doing weekly water changes (30-50%) until you get a handle on those parameters.

 

[kaliya]

I probably did overfeed, I admit that, especially with so few fish in the tank. However, the problem only started right after cleaning, and I couldn't see any uneaten food on the bottom.

I tested the water again after the issues started. Tests for hardness and ph were slightly unsafe/high, but the rest were in safe range. I will test again today and see what I get.

 

[Fresh2o]

Not sure why the fungus would appear so quickly after it being relatively clean.
Fish will be fine with light feedings. Rather than removing the gravel, get a gravel vacuum and use it while performing water changes.
As for water testing, liquid based tests are more accurate than the test strips. Initially the cost might be higher, however, the number of tests that can be performed from a kit (such as the API Freshwater Master Kit) will offset the cost per test ratio. At this point I would be concerned with (in order): ammonia, nitrite, nitrate, GH/KH (hardness).

 

[jarrod0987]

I have seen some bacterial masses that look somewhat like this when I set up my dirted tank. I did not try to remove them. They went away on there own after a few weeks. I can't say It looks exactly like what you have.