3 fish unresponsive surrounded by 2 days- please give a hand?

Yesterday i discovered that 1 of my platies was dead about a week after buying it. I rapidly tested the water ( i dont have ammonia test) and the nitrates and nitrites were a touch high, but not very high. So i did a dampen change- today I discovered a sailfin molly and a yellow cobra guppy also dead on the floor of the reservoir. No marks on their bodies, like the platy.(I have conducted another marine change today, just within case) I was wondering what this was due to- my water is crystal clear. The individual thing i though that maybe the fish had'nt been getting ample food- the molly hadn't as she had given birth as soon as in tank, and afterwards not eaten much. The guppy I thought had had like mad of food but had actually lost his colour, when I put him in 2 weeks ago he be bright yellow, he was very sickly yellow before he died. The platy I thought had be getting enough food, but I do have 5, so I may have mistaken him/ her for a different one. I be wondering whether you can see anything that signifies why 3 of my fish have died in 2 days when the tank have been reading fine on its tests, the water be crystal clear and all the fish seemed healthy.

Thanks within advance for your time.
have you checked that your water is,nt to soft.ph contained by a community tank should be about 7-5 for the fish you are keeping.if it is at an Extreme.e. too soft consequently this could be the problem.
Sorry for your loss but you really entail to quarantine new stock for about 2 weeks before putting within with your other fish, your molly also needed to be put in a hospital/ quarantine tank to recuperate after giving birth, we have all been where on earth you are once upon a time but we learn through our mistakes.
Quarantine is a must. Hope this helps
Take a water sample to a pet/fish store. Are you using any hose conditioner when you change the water?
There is Probably a disease in the tank simply bring a sample to the pet store it could be over crowded in the tank so see but the creature says at the pet store
Nitrite level should be ZERO, whether your tank is cycled and running correctly. The NItrate isn't so important, 10-30ppm is normal.

If you enjoy a nitrite reading then it's also likely that the tank have some ammonia in the water too.

As an emergency measure, do some considerable partial water changes, 30% per day, to amend the water conditions.

Get an ammonia test as well so you can see precisely what is going on.

The frequent water changes are just an emergency fix to hold your fish alive untill your tanks cycle settles down, may take a couple of weeks.

Ian
dead fish happen because of
1 disease
2 the tank is not cycled
3 your nitrate nitrite and ammonia are to big
the fact your tank has elevated nitrates and nitrite suggest that was what killed your fish
your level should always be at 0
Answers:    The obvious cause have to be your water quality and an ammonia test would hold been useful. Sniff your water, does it smell and do you enjoy a PH reading? An ammonia spike will raise your PH.

The other possibility is this new Platy be diseased, are there any signs of illness in your remaining fish?

Hi there,

one request for information that springs to mind is...how long has the tank be set up?

A tank takes approx 6 weeks to cycle properly. By adding too plentiful fish into the uncycled tank will cause an overload to the filter. I can suggest a 'type of remedy' if your local fish shop sell it. Its called 'Bactinettes', you tag on it to your filter sponge and it starts to break down the ammonia ( if present!) and that will in turn break down the nitrites etc etc. Be sure to bring back the ones that look like little black pearls though as the sand one doesn't work very well. Also, they want to be kept in the fridge so that bacteria doesnt die.

Also on a personal recommendation i would use 'nutrafin aqua plus', its much better that the tetra ( as i articulate, personal recommendation!) and its also is more concentrated so lasts longer.

the platy that you brought may have be in a contaminated tank and with bringing it domestic in the water that it comes in and next you put it in the tank may have contaminated your reservoir so no matter what you could have done the fish would have died hope this help u out do weekly changes 25% do not add any more fish for at least 1 month using the tetra aqua undisruptive good luck
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