I had two fantails for for about 3 weeks, and one of them died yesterday. He darted around the tank very quickly, but with little control (sometimes would flip upsidedown).

I'm worried about the other one dying too.

My test kits can't pick up any ammonia or nitrites and the pH has been between 6.8-7.0 (I know, I'm trying to bring it up). When I got them, the cycle wasn't established yet, so that could be a factor for a lot of stress. I did have some rocks (about a cup or so) from an established tank.

They both were very healthy up until two days ago, when the first one that died started acting lazy.

The remaining fish has the following symptoms:

- Stays near the bottom of the tank primarily (he can go to the top and sometimes does).

- Loosing some color on his face under his eyes.

- Startled easily.

- Lowered appetite.

- Will sometimes dart around the tank, but has more control than the one that died (for now at least).

Is it a disease? Is it just stress? I've added stress coat to their tank as well as some aquarium salt.

Any ideas on how I can treat him?

Thank you

Some other info that might help:

The tank is a ten gallon tank and the fish is very small (about 1" - 1 1/2" long).

I've been feeding him a mix of goldfish flakes, goldfish color enhancing pellets, goldfish sinking sticks, blood worms, and sweet peas.

Except for the color loss I already mentioned, there's no unusual findings. His fins are all in good condition.

I've been changing about 3-4 gallons every 2-3 days since the cycle hadn't established yet.

The filter is a power filter with a bio foam and a bag of ammonia chips.

I treat my water with Amquel Plus and pH buffer 7.5 and let it age for at least 24 hours before using (usually much longer).

sounds like a water quality issue. i think not cycling the tank is a factor but have you tested your nitirates? if they are too high they can be harmful to your fish just as much as ammonia or nitrites.

The nitrate test I did this morning looks like the 0 color, but I guess it could be as high as 0.5 ppm since the colors are in increments of 5 ppm.

THis morning he was pretty bad, but he seems to be doing much better the afternoon. I was able to feed him some blood worms. He's still pretty jumpy, though.

That kind of behaviour *definitely* suggests water quality problems.

Does the pH stay absolutely steady at 6.8 or does it fluctuate? What have you been doing to bring it up? Pale patches on the skin often indicate a problem with the pH you see.

Are there definitely no ammonia / nitrite readings? If the tank has not cycled I would expect there to be some at least. Nitrates you don't have to worry about - goldfish are happy up to about 40ppm (though less than 20 is best).

Do you de-chlorinate the water every time you do a water change?

Sorry for all the questions!

I keep a bunch of 1-gallon jugs around with water that I've treated with amquel plus and proper pH 7.5. This is the only water I use to make changes.

The pH has been fairly steady for a while at around 7.0 but lately even with pH buffer in addition to what is in the replacement water, it has been hard to keep it steady. I've seen it dip once as low as 6.6.

The ammonia / nitrite levels have been steady for about 3 or 4 days now, but there were increases before that I treated with water changes and amquel.

I have no problem answering questions, anything that can help I'm more than happy to do!

Thanks for answering.

OK, the first problem is the pH swings. There is a huge difference between a pH of 6.6 and 7.5 - more than enough to stress the fish badly, especially if the pH is shifting up and down most of the time. This is probably the main cause of the pale patches and frantic behaviour.

The problem is that Proper pH Up only increases the pH level - it doesn't actually hold it at a constant level (common misconception). What is lacking in your water is not pH but buffering capacity, which is closely related to water hardness (the KH of water). Buffering aloen is what keeps pH up and steady. Therefore, hard water with a high KH will have a completely steady neutral to alkaline pH. Soft water with a low KH will have a constantly shifting acid to neutral pH. So, what's happening in your tank is that you keep adding the pH Up agent so the Ph level shoots up, but then immediately it starts falling back down again because there is no buffering capacity to hold it steady. The result is a very uncomfortable chemical rollercoaster ride for your fish.

The quickest way to artificially buffer water is to add ordinary baking soda to the tank. Add it one teaspoon at a time, testing the pH and KH (you'll need a test kit for this) as you go until the pH has reached a level of about 7.6 or so and the KH is over 80. The soda will now hold the pH rock-steady at that level until your next water change. A less time-consuming way of buffering is to add crushed coral or oyster shells to the filter. These work in exactly the same way, but you don't need to worry about adding more every time you do a water change, as you would with baking soda. Just replace the coral or shells as their efficacy diminishes over time.

When the ammonia and nitrite levels rose a few days ago, how high did they get? And how often / how much water have you been changing since?

The ammonia level would sometimes get as high as .5 ppm. I've been changing about 3-4 gallons of water (and vacuuming the gravel) every 2-3 days.

Thanks for the advice about the water hardness, I'm off to get some crushed corals or oyster shells. I'm hoping I can find a KH test somewhere. I've been to two of the four pet stores around and I've had no luck so far.

Oh, and should I add a buffer to the water jugs?

An ammonia level of .5 would not hurt your fish - it's only when it gets above 2 or even 3 that fish start to suffer - so I'd say the pH is definitely the cause of your fish's symptoms. BTW, don't vacuum the gravel too much during cycling as the gravel itself holds a colony of biobugs which help to get the cycle established.

If you have crushed shells or coral in the filter then there is no need to buffer the jugs as well. If you use baking soda though then yes you would need to add some to the jugs every time you do a change because some of it would be lost in the water you take out.

NB: When you use buffering agents like soda or shells these raise the pH as well as the KH, so you don't need to add pH raising agents as well as buffering agents.

Well thanks for the help! I can save some money on pH buffer at least .