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Aquarium Advice Apprentice
Feb 23, 2024
105 lt fresh water tank..ammonia levels high and water cloudy for weeks.
I have changed 25% water twice weekly
Hoovered up gravel and waste weekly
Reduced feeding
Only have 12 small cold water fish 2 fantails
P H 7
Nitrites and nitrates normal
Filter constantly on.
Air stone on
Temp at 21 deg
Added bio start bacteria

But still high ammonia and cloudy water

Why won't the water clear?
How long has the tank been set up?

What precisely are your water parameters?

What test kit are you using?
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How long has the tank been set up?

What precisely are your water parameters?

What test kit are you using?

Set up 3 months. But recently did a complete emptying and washed gravel, 2 weeks ago because I couldn't understand why the ammonia levels were so high. So eliminated that it might be detritus in the gravel
Really need the numbers on the water tests to see exactly where you are, preferably before a water change. pH, ammonia, nitrite. If you know your carbonate hardness, that would be useful too.

Cycling a tank can take months, and the growth of those microbes are temperature dependant. It can easily take a couple of months at 28c, at 21c i could see it taking 6 months to cycle a tank.

You have a lot of fish for an uncycled tank. 100 litres/ 25 gallons should only have a couple of small fish in an uncycled tank, so its not a surprise if you are seeing high ammonia especially as goldfish are very messy fish.

Really all you can do is regular water changes and have patience. If your ammonia tops 0.5ppm change water. Your cleaning could easily have started your cycling process from scratch.
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Ph 7.0
High range Ph 7.4
Nitrites .50
Ammonia 2.0

Temp 21 c
Your cycle has established to some degree because you are seeing nitrite. The presence of nitrite can cause false positive readings on the nitrate test, so there is no point testing for nitrate until the water is free of nitrite as you cant trust the result.

The ammonia is too high. Take your ammonia result and nitrite result and add then together. So in your case thats 2.5. You don't want that combined total to be higher than 0.5. So you need to do some pretty big water changes. Based on those numbers 2 or 3 50% water changes should get your water quality back to a safe level. Do them an hour or 2 apart. Test daily and if the combined result is above that 0.5 combined target change enough water to get below that target.

This is the result of having a lot of fish in an uncycled tank, you typically want 1 small fish for every 40 litres/ 10 gallons of water when you arent cycled and then gradually increase the numbers of fish. But we are where we are and you have to make the most of it. Cutting back on feeding the fish will help with water quality as will a more frequent water change schedule.

To give you some comfort ammonia toxicity is temperature and pH dependant. The higher the temperature and the higher the pH, the more toxic the ammonia you are detecting becomes. At your temperature and 7.4 pH ammonia starts to get toxic at around 4ppm. If your temperature was around 24c you would be seeing health issues with your fish, so the temperate water conditions are saving your fish in the poor water quality.

This thread explains ammonia toxicity in more detail.
Thanks. Just done a 25% water change. So will repeat that frequently as you advise. And keep the temp down to around 21 or less.
Also will only feed once a day. Hopefully when I'm on holiday in 4 weeks I will be more reassured the right things are happening !!
25% water change removes 25% of the waste, so a 25% water will reduce the ammonia from 2ppm to 1.5ppm which isnt going to help a lot, and tomorrow it will likely be back at 2ppm. In the short term you need to be doing bigger, more frequent water changes than 25% every day. I would do at least 2 x 50% water changes today and then see what your water quality is like tomorrow and base tomorrows water changes on the result.

This is why you dont want a lot of fish in uncycled tanks, because the water quality deteriorates quicker than a reasonable water change schedule can compensate for, so you end up doing multiple, big water changes everyday until the tank starts to cycle.
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Hi thanks. I have now completed a 50% water change. I needed to get more Aquasafe. Will test quality tomorrow as you suggested.And repeat until I get down to safe levels.
Seems a bit illogical that 50% water changes are more effective than 100% as I did before. But guess I know nothing about chemistry going on in the tank.
After 1 x 50% change see pic
Hardly changed.
Doing another one.
A 100% water change will be more effective than a 50% water change, but the only way to do a 100% water change is to remove all the fish which isnt going to be good for the fish.

You have never mentioned 100% water changes before. Just a complete emptying when you cleaned it. That would just lower waste temporarily, but as you arent cycled it would just start to rise again as soon as you returned the fish. Its regular water changes you need to keep on top of the elevating water parameters between water changes.

Can you test your tap water as well when you get a chance. Add some water conditioner before testing the tap water. If your water is treated with chloramine rather than chlorine the chloramine will be showing as ammonia.
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Yes I did a 100% water change last week and washed all the gravel clean after removing fish. Tested the tap water and it was ammonia free. Crystal clear for 2 says then cloudy again and ammonia reading high.
Only fed once a day a tiny amount.
Washed one filter in aquarium water and left the other. Added a bag of Fluval ammonia remover in the tank also.

I have tried everything.....
The cloudy water is called a bacterial bloom, and is bacteria feeding off nutrient imbalances in the water and growing in such numbers that they become visible. As the tank cycles and denitrifying bacteria establish, the bacteria causing the cloudiness will be outcompeted and die off. What you are seeing is normal in an establishing aquarium.

As said, cycling an aquarium at low temperature will take much longer to cycle than one at tropical fish temperature. If you are doing a fishless cycle you want the temperature up around 28c, with temperature water fish you will need patience as it could easily take 6 months.

Adding ammonia removing media is a bad idea. It will starve the microbes you are trying to grow and your tank will never cycle. You need to control the ammonia to a safe level through water changes.
That's interesting re the bag...I have removed it now.
My ammonia levels are now .25 and
Nitrites 0
nitrate 5.0

There is a green bloom growing on the inside glass.
Should I remove it? Or is it a good sign?

Ammonia is at a good level now. See what it is tomorrow.

The green on the glass is algae. If you have light and nutrients you will get algae. Its neither good or bad, its just what happens. You can wipe it off if you dont like the appearance or leave it if thats your preference. Wipe it off before a water change, so you remove the algae spores when you remove the water.

Controlling algae can be achieved by controlling light and/ or nutrients. Keeping up with water changes and not overfeeding will keep nutrients at a low level. Keep your aquarium away from natural daylight, and if you dont have live plants you dont need aquarium lights on all that much.

Some fish and inverts eat algae too. You would need to be careful as to whats compatible with goldfish and your water temperature though. Maybe nerite snails are the best option.
Thanks again Your advice has given me more confidence and I was beginning to give up on the aquarium.
I will keep checking the levels and doing water changes over the next few days when necessary.
Also the light . I was told fish need 8 hrs of daylight???
My tank has white and blue lights. Is the blue uv light better?
Fish dont need the light on at all. Plants typically need 6 to 8 hours a day. Having zero lighting might cause the fish to not colour up the same, but they don't really need the light on and will do fine with just the room lighting. The light is for your benefit of enjoying watching your fish, and most aquarium plants need artificial lights assuming the aquarium isnt sat in daylight.

The blue light isnt likely to be UV. If it is, then throw it away as it can cause cancer in your fish same as sunbed use can cause cancer in people.

Generally the blue setting on an aquarium light is just low level blue light that you can use as a night mode. Blue light wont cause any algae growth, but you also wont be able to see your fish very well. Stick with the white light on a timer for when you are generally at home, the longer you keep the light on, the more algae will grow. Try and keep the timing regular with a timer, rather than just turning them on manually when you feel like it. 6 to 8 hours a day shouldn't cause too much algae. You can have them on longer if you prefer, but make sure you 8 hours of nighttime.
50%water change today after testing ammonia levels which were back to the same reading as before a 2x50% water change yesterday!!!!
I will do another 50% change later today.
This method is not working...
Yes the level drops, only to go back up a day later.
Obviously just diluting a continuing problem. ?
As said, you could be doing this for another 6 months until the tank cycles. There is no shortcut.

Cycling a tank with fish entails frequent water changes until the tank cycles. Its not a quick process and at your low water temperature will take longer than it would at tropical water temperatures. The high number of fish means you need to do bigger, more frequent water changes than would be the case if you had only a couple of small fish as recommended.

If you want to get rid of the fish and do a fishless cycle thats a different process and will probably be quicker, but still possibly another month or 2.
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On the positive side the water is fairly clear but guessing that is obvious as I keep changing it. There isn't any bacterial bloom going on. Just high ammonia.
Do I change the filters or just leave them. Usually I wash them in tank water once a week as they are fairly grimey.
I have nowhere long term to keep the fish so it will have to be the long game. If it wasn't for testing the water every day I wouldn't know there's a problem as the fish seem healthy.

Seems like I have made a rod for my own back by caring too much.

Hey ho. Time for another change of water.
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