2nd Bloom

[RobVG]

2 Fancy goldfish, 16-gallon tank, under-gravel filter, water parameters nominal.

Set the tank up and cycled it naturally about 6 months ago. Had a bloom after a couple weeks. Did regular water changes and the bloom continued for 3 weeks and then cleared up on its own.
Now the water's cloudy again. It's been about a week and a half. Should I just wait until it passes? It' pretty discouraging.

 

[Colin_T]

What sort of bloom, algae or bacteria?
Algal blooms are green, bacterial is cream/ white.

Picture showing the entire aquarium so we can ID the issue and see how big the fish are compared to the tank?

What is the ammonia, nitrite, nitrate and pH of the water?

How often do you do water changes and how much do you change?
Do you gravel clean the substrate when you do a water change?
Do you dechlorinate the new water before adding it to the tank?

How often do you feed the fish?
What do you feed the fish?

 

[fishorama]

Like Colin asked...But I have to say even 2 small goldfish in a 16g isn't a long-term tank for them. The "usual" recommendation is 30 gallons/per goldfish or more. Make a plan!

 

[RobVG]

What sort of bloom, algae or bacteria?
Algal blooms are green, bacterial is cream/ white.

Picture showing the entire aquarium so we can ID the issue and see how big the fish are compared to the tank?

What is the ammonia, nitrite, nitrate and pH of the water?

How often do you do water changes and how much do you change?
Do you gravel clean the substrate when you do a water change?
Do you dechlorinate the new water before adding it to the tank?

How often do you feed the fish?
What do you feed the fish?

 

[RobVG]

It's milky.
Nitrite and Nitrate levels are very low. PH 6.8. I use test strips that don't read ammonia.
I vacuum the gravel during weekly water changes. I do add conditioner to remove chlorine.
They've always been overfed- my wife is the culprit.

I don't really want to pinpoint the cause, I'd like to know all the causes so I can learn about them. I just find it strange that it was clear for 6 months then all of the sudden got cloudy.

Because of the low nitrite/nitrate levels I'm starting to wonder if something has killed off the nitrogen cycle.

 

[Colin_T]

The main causes for milky cloudy water is a new filter (filter without enough beneficial bacteria) or uneaten food rotting in the tank.

The tank has been set up for a while and is using an undergravel filter. These are pretty stable filters once established and the only reason they die is from chemical medications or not being gravel cleaned.

Without knowing the ammonia level (it's probably 0ppm due to the tank being set up for over 6 months and having an undergravel filter) I would say it's caused by uneaten food. Uneaten flake or pellet food will cause milky cloudy water. A gravel clean and big (75%) water change usually fixes it.

 

[RobVG]

The main causes for milky cloudy water is a new filter (filter without enough beneficial bacteria) or uneaten food rotting in the tank.

The tank has been set up for a while and is using an undergravel filter. These are pretty stable filters once established and the only reason they die is from chemical medications or not being gravel cleaned.

Without knowing the ammonia level (it's probably 0ppm due to the tank being set up for over 6 months and having an undergravel filter) I would say it's caused by uneaten food. Uneaten flake or pellet food will cause milky cloudy water. A gravel clean and big (75%) water change usually fixes it.

Thank for the input. I may have found the cause. We bought a new ornament from the dollar store. It looked just like the ones sold at Pestsmart. I realized the cloudiness started shortly after we added it. Should I do more frequent water changes to rid the tank of any chemicals leached from the decoration?

 

[Colin_T]

Yes, it's a good idea to do a 75% water change and gravel clean the substrate every day until the water is clear.

You can test the item by putting it in a clean container of water and see if it makes the water cloudy. if it does, then it should be returned because it might not be safe for the fish.