Cloudy eyed white goldfish

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Aquarium Advice Apprentice
Aug 7, 2021

My son’s fair time goldfish is my little buddy and I’ve kept him alive 3 years so far, but he’s becoming ill and I desperately need help. Please be kind, fish are NOT my area of expertise and passion but I’m doing my best.

He’s in a 20 gallon aquarium with an albino pleco. We have an appropriate filter and a bubbler, and a heater set to 70 degrees Fahrenheit. I use bottled RO water to do 50% water changes every week or two. Add API Quick Start at each water change. Filters are changed as recommended.

When we got the 20 gallon tank about a year ago, we put seashell type substrate in the tank. The goldfish gradually turned white but seemed very healthy. I read on what could be turning the goldfish white and alkalinosis seemed like the diagnosis because of the substrate, and because the PH was getting higher, and PH Down didn’t touch it (PH was like 8.0) So I scooped out all the seashell substrate this weekend and netted the fish/removed them from the aquarium when I did this. I then performed a 50% water change as usual and replaced the filters. We now have standard aquarium rocks. I did not add Equilibrium this time around as I thought it might help with PH, but I usually add the recommended amount at each water change to remineralize the water.

The pleco seemed lethargic yesterday but that’s kind of her personality so I didn’t think much of it, but today, the goldfish has cloudy eyes and is extremely lethargic.

All readings are:
PH: 7.4
Ammonia: 0
Nitrite: 0
Nitrate: 0
GH: 180
KH: 120

In case this is a case of the net causing injuries, I added a dose of Melafix this evening and will follow the recommendation for a 7 day course followed by a 25% water change in 7 days.

Any suggestions? I’m grateful for your help. Feeling really anxious and worried about our little friends tonight.
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There is a problem with your water parameters.

The nitrogen cycle turns fish waste (ammonia) into nitrate. So a cycled aquarium will have zero ammonia + nitrite, and some nitrate. An uncycled tank will have ammonia and/ or nitrite depending on how far progressed your cycle is. You are reporting zero across the board, which is impossible unless you did the test immediately after a near 100% water change. Goldfish and plecos are very messy fish, each on its own will be producing a lot of waste, together in such a small tank they will be causing water quality issues which somehow aren't reflected in your water parameters. My thoughts are there is something wrong with your water test and this could be hiding a water quality issue.

After a year, the liklihood is you are cycled and nitrate is a possibility for being incorrect. What test kit are you using? Are you sure you are doing the test correctly? Can you get a 2nd opinion on your water parameters, preferably not immediately after a water change? Fish stores can usually do this for you.

There is a lot going on here, and going back over your post history there is a clear issue with the goldfish being kept in an unsuitable home. Goldfish can get really big, but they arent really suited to aquariums. 20g is the minimum for a goldfish, but that is the minimum and for most of its life the goldfish was kept in an even smaller space. This causes stunting, which in turn leads to ill health and shortened lifespans. A 3 year old goldfish should be 12 inches in length if allowed to grow properly. 3 years is a decent age for a fairground goldfish kept in a small aquarium. The turning white could have been a natural aging process when being kept in a minimum environment.

What you did then was to change the water chemistry overnight. You removed all the things that was raising the hardness and pH, did a big water change with RO water and didnt remineralise as you normally do. When you returned the fish to the aquarium it went back into water that was very different to what it came out of and that is a shock to the system that fish often dont recover from. Apart from the colouration you wasnt having any issues until you tried to change things.

Melafix isnt going to help with anything. Its just teatree oil, so consider it a herbal remedy. It might help prevent infection in an injured fish, but isnt going to cure anything.
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