Multiple fish casualties

[Characf]

Hello im relatively new to fish keeping and was doing well for the first month or two, but all of a sudden I've had 6 dead fish 4 guppies and 2 platies. 0ppm of ammonia, but my Nitrates are about 40ppm.

I'm doing a 60% water change as I haven't done it in two weeks and hopefully that sorts the issue, but I'm really not sure as my other fish aren't showing signs of gasping etc.. I noticed before said fish died that it was swimming on its side and then being picked on

 

[Characf]

Notes- The lid broke so I've got a bit of wood over the top atm and algae bloom? Would these factor

 

[Uberhoust]

Notes- The lid broke so I've got a bit of wood over the top atm and algae bloom?

I have had tanks go solid green just about, with algae, with no apparent stress on the fish. Obviously if you are having a cyanobacteria bloom of that magnitude you could have some issues.

The wood over the aquarium is unlikely but possible suspect. Even if the wood is not treated and a species that is typically ok for aquarium use it can still be a hazard. All sawmills, except specialty mills, use a mixture of oil and water to lubricated the saws. Additionally, there are possible contamination from hydraulic fluids, petroleum products etc. from handling and in the yard. These contaminants are not in large amounts but you could have a piece that was showered with hydraulic fluid when a hose or seal broke. It would depend if the wood is untreated and fully exposed to the water, or if it was sealed in some fashion. I would not use commercially sawn lumber in a wetted environment with fish. Not saying it is the cause but it could be.

 

[Slaphppy7]

What kind of test kit are you using? What kind of water conditioner?

Was the tank cycled before adding fish?

 

[Byron]

First, your water changes need to be more regular, at the very least once a week when thing are "normal." And change 50-70% at each, provided the parameters are the same between tap and tank water, and parameters means GH (hardness), pH and temperature.

Second, nitrates at 40 ppm are way too high. This is not likely to kill fish this quickly, but it is a very negative factor. Nitrate is poisonous to fish, it just is slower-acting and depends upon the level, the exposure time, and the species. But you want nitrates as low as possible, meaning zero or as low as possible. On this. have you tested the tap water on its own for nitrate? If nitrate is coming in with fresh water, that is one thing, and if nitrate is occurring within the biological system of the aquarium that is another.

Having said the above, I would suspect either something toxic in the water of the aquarium harming the fish, or diseased/injured fish themselves, so some questions:
Ammonia you say is zero, what about nitrite (with the "i")?
How long has the tank been running, and how did you cycle it.
What additives/substances are you adding, including conditioner, water treatments, plant fertilizers, etc.
What is the GH and pH of your tap water on its own?
What is the tank size, and please list all fish (species and number of each).

 

[Characf]

API master test kit, tetra aqua safe and yes I cycled it for about a month and had lots of growth on plants and 0 ppm of ammonia and still is? I'm feeding my fish every 2 days a small pinch and some sinking pellets you don't think they're starving to death do you I got told not to over feed.

 

[Characf]

How long does a Platy and Guppie live? I've had them a few months now and pretty big when I got them

 

[Byron]

Notes- The lid broke so I've got a bit of wood over the top atm and algae bloom? Would these factor

Please explain this more fully so we know what it is.

 

[Characf]

Just green algae on all the wall, I've cleaned the front and left it on the other sides but I've noticed some dark green/black type mold that's growing on a plant could this also be a factor. I've attached some photos, excuse the mess I'm in the process of a 75% water change

 

[Characf]

Photos

 

[Characf]

Weird thing is I have other platies and guppies and they appear to be fine?

 

[Characf]

First, your water changes need to be more regular, at the very least once a week when thing are "normal." And change 50-70% at each, provided the parameters are the same between tap and tank water, and parameters means GH (hardness), pH and temperature.

Second, nitrates at 40 ppm are way too high. This is not likely to kill fish this quickly, but it is a very negative factor. Nitrate is poisonous to fish, it just is slower-acting and depends upon the level, the exposure time, and the species. But you want nitrates as low as possible, meaning zero or as low as possible. On this. have you tested the tap water on its own for nitrate? If nitrate is coming in with fresh water, that is one thing, and if nitrate is occurring within the biological system of the aquarium that is another.

Having said the above, I would suspect either something toxic in the water of the aquarium harming the fish, or diseased/injured fish themselves, so some questions:
Ammonia you say is zero, what about nitrite (with the "i")?
How long has the tank been running, and how did you cycle it.
What additives/substances are you adding, including conditioner, water treatments, plant fertilizers, etc.
What is the GH and pH of your tap water on its own?
What is the tank size, and please list all fish (species and number of each).

I've answered this on all previous posts and use your nitra zorb filtration process. I didn't test for Nitrite as if ammonia is 0 surely it means I've not going Nitrite? And I do usually do a 30% change weekly but I've had a hectic few weeks so just left it.

 

[Byron]

The fuzzy algae on the plant leaves is black brush algae. This is what I term a "problem" algae, and like all problem algae, when it appears in a planted tank it means the natural balance of light and nutrients is not in sync, so the balance has to be restored (or established). The intensity and the spectrum of the light factor in, and then duration. You have not answered many of the questions asked, we need all this data to bee able to logically provide help. And nitrites can be present with zero ammonia, and very low nitrate. All tests are necessary so we have all the facts. And I see nothing about nitra zorb.

 

[Naughts]

Nice tank and plants! When was the last time you added fish or plants? If this coincides with the onset of problems it could be that a disease or chemical was introduced. Do you quarantine new fish?

 

[Characf]

The fuzzy algae on the plant leaves is black brush algae. This is what I term a "problem" algae, and like all problem algae, when it appears in a planted tank it means the natural balance of light and nutrients is not in sync, so the balance has to be restored (or established). The intensity and the spectrum of the light factor in, and then duration. You have not answered many of the questions asked, we need all this data to bee able to logically provide help. And nitrites can be present with zero ammonia, and very low nitrate. All tests are necessary so we have all the facts. And I see nothing about nitra zorb.

So I use nitra zorb to get nitrates out my tap water as its about 30ppm straight from the ta

Nice tank and plants! When was the last time you added fish or plants? If this coincides with the onset of problems it could be that a disease or chemical was introduced. Do you quarantine new fish?

Thanks, I haven't added anything new fish or chemical wise