Newbie with a Fungal Issue

[Addison Rains]

I've been given over command of a 30 gal tank. The fish went with the previous owner but the tank remained, covered completely with algae. So I changed out all the water, scrubbed the rocks and fake plants with water and a splash of bleach, added water to the gravel and cleaned it the best I could. Then added water, Amquel, put everything back, got a brand new filter (Marineland Penguin 150), a heater (currently at about 77 degrees), and let the water cycle for about 3 weeks. Then, at the suggestion of a friend, got 5 striped danios to start getting the ammonia going.

It worked for about two weeks, they were healthy and the water was starting to cloud like my friend said it would as the ammonia blossomed. But then a fish died, then another within a few hours. I took the water to be checked at a pet store and they said the ammonia was still too high. I needed to add bacteria to the filter and media. I did. Next morning, all the fish were dead. The ammonia was still too high. So I added more bacteria a week later and let it cycle for another week.

Yesterday I bought new fish and put them in: 2 mollies, 2 platys, and 3 Barbs. I put their bags in the water for about 30 minutes to acclimate to the tank temperature then slowly added tank water to their bags before adding them in. 12 hours later, one barb is barely alive and everything else is covered in this white stuff. Its the same stuff that covered the danios when they died. I thought it might've been the bacteria having a hayday but now I don't know. It's not Ich, but if its fungal I have no idea what sort and how to fix it.

I never had this issue with brand new tanks and goldfish.

Any advice would be so helpful! I'm close to just emptying the tank and putting in hermit crabs! But I love fish!

 

[Rbishop]

What "bacteria" did you add?

Readings on your tank and tap water from a good liquid test kit?

Letting the tank run for three weeks, doesn't "cycle" a tank.

Frequent water changes of 30-50% as needed by ammonia readings is needed as the tank cycles with fish in it.

 

[Tifftastic]

What you're seeing is what happens to fish when they die. The fuzzy looking stuff is their slime coat thickening as the fish starts to decompose.

I recommend reading on the nitrogen cycle. But basically what happens is that the fish produces ammonia, a bacterial colony forms that eats ammonia and produces nitrites, another bacterial colony forms that eats nitrites and produces nitrates, nitrates can only be removed by water changes or plants. Ammonia is incredibly toxic, nitrite is incredibly toxic, nitrate starts to get toxic at prolonged exposure above 20 ppm.

Letting water circulate through the filter for 3 weeks with no fish or food waste, isn't cycling the tank. The bacterial colonies won't grow, because they have no food.

What you are doing now is a fish in cycle and to combat the toxicity of the ammonia you will need to be doing daily water changes.

I recommend doing three things immediately:
1) change 50-75% of the water right now
2) order an API master test kit (the liquid one)
3) google "nitrogen cycle"

Do these things in that order.

You'll need to do a 50% change likely daily until your test kit arrives. When it arrives, immediately test your ammonia. Then keep doing daily water changes until the ammonia stays at zero. Once the ammonia gets to zero then test your nitrites and keep doing daily changes until this stays at zero, then test your nitrates and keep changing water daily until the nitrates are consistently under 20 ppm. Then you will know how much water you need to change weekly to keep the nitrates under control.