Ive lost 3 fish in 3 days...no warning and no signs of illness till a few hours then they go downhill fast. My water readings are good and Ive done a pwc. Ive recently finished with a course of ich treatment but the fish that have died wasnt the ones with ich. Im getting pretty worried as one of my balloon mollies just got stuck on the pump outlet. Its like she hasnt got the strength to swim against the current and she seems very lethargic. I think Im going to lose her too :( What could be wrong with them? Please help!

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thanks
Karen
200 liter tank, jbl canister filter, hydor external inline heater containing:
3 dalmation sailfin mollies
2 saffron balloon mollies
3 sunset platies
10 neon tetras
4 male guppies
3 panda corys
2 spotted corys
2 leopard plecos (rehoming soon)
2 mosaic gouramis
3 dwarf gourami
5 pink tetra
5 glass catfish

40 liter with 7 molly fry and a bumblebee shrimp
:fish

What are you water readings? How big is the tank? How much water did you change? What are you feeding them?

Water readings are nitrites 0 ammonia 0 nitrates 17. Tank is 200 liters. I changes about 30% of the water. They get a small pinch ofjbl flakes and one jbl sinking tablet once a day and 1 algae tablet once every 3 days plus the occasional spinach, peas or cucumber. Oh and once a month freeze dried bloodworms.

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thanks
Karen
200 liter tank, jbl canister filter, hydor external inline heater containing:
3 dalmation sailfin mollies
2 saffron balloon mollies
3 sunset platies
10 neon tetras
4 male guppies
3 panda corys
2 spotted corys
2 leopard plecos (rehoming soon)
2 mosaic gouramis
3 dwarf gourami
5 pink tetra
5 glass catfish

40 liter with 7 molly fry and a bumblebee shrimp
:fish

Ever notice the crab making any advances toward the fish? There have been many instances on this forum where creatures like that have killed fish in the tank with them. The problem is at night your fish sleep and the crab continues to do his thing. A sleeping fish is an easy target.

Often, an ich outbreak is a secondary problem that appears because something else was wrong - either another parasite, or a bacterial infection. Balloon mollies are often open to this as they are bred with a deformity that makes them start out life with problems - any deformed fish is at a disadvantage when there is a problem in the tank.
Are the losses all one species or type of fish, or are they spread across all the types of fish you have? I was having difficulties with a group of livebearers dying suddenly without symptoms - healthy looking one day and dead the next - until a friend did an autopsy on one and found it was infested with worms. I treated for internal parasites and it seems to have worked. The worms seemed to have stayed with the livebearers and didn't cause any losses in the other fish with them.
There's no guarantee that's your problem, but it would be good to know exactly which species are dying here. As hobbyists trying to care for our fish, our best hope is often the ability to spot patterns.

I should have said that the crab is no longer in the tank, a good friend took him as he did start to get a bit too territorial. I think its wrong that they breed fish that suffer with such health problems as a balloon molly does. The same one who is poorly now had a swim bladder problem just before xmas but it was sorted out with some peas and some quiet time in the floating baby tank. I will not buy anymore. My fish that have died so far have been a dwarf gourami and two platys. The balloon molly is still hanging in there but I dont expect here to be alive in the morning :( I will look into treating the fish for parasites thanks though Ive just finished treating for ich and dont like using chemicals. Maybe I should run some carbon in the filter for a while before treating again?

__________________
thanks
Karen
200 liter tank, jbl canister filter, hydor external inline heater containing:
3 dalmation sailfin mollies
2 saffron balloon mollies
3 sunset platies
10 neon tetras
4 male guppies
3 panda corys
2 spotted corys
2 leopard plecos (rehoming soon)
2 mosaic gouramis
3 dwarf gourami
5 pink tetra
5 glass catfish

40 liter with 7 molly fry and a bumblebee shrimp
:fish

Well, now that you've updated your stocking list...you are trying to put way too many fish into that size tank. Dwarf Gouramis are very territorial and if they are all males, you'll soon just have one....after he has killed the others.

Your fish are probably dying from stress. Stress brought on by overcrowding, I believe. Probably not what you want to hear.

Really Im over crowded??? in a 200 liter tank?? really doesnt look so many and I thought I had calculated right. My tank is 100x50x40cm. I only have one male dwarf gourami the other two are females and they seem to get on ok.

__________________
thanks
Karen
200 liter tank, jbl canister filter, hydor external inline heater containing:
3 dalmation sailfin mollies
2 saffron balloon mollies
3 sunset platies
10 neon tetras
4 male guppies
3 panda corys
2 spotted corys
2 leopard plecos (rehoming soon)
2 mosaic gouramis
3 dwarf gourami
5 pink tetra
5 glass catfish

40 liter with 7 molly fry and a bumblebee shrimp
:fish

44 fish in a 44 gallon (200L) tank is WAY too many. There will be deaths until the tank is less crowded and the more territorial members sort out enough room for themselves.

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Officially fishless until after the move....tune in later for details!

Even if you calculated using the 1 inch rule, you are over stocked. most of the fish you have is going to be 2 inches and some even more. And going by the 1 inch rule you basically have like 80 inches of fish in there.
Besides the 1 inch rule basically applies to fish like the neons, not the others.

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SUCCESS IS MEASURED BY YEARS, NOT MONTHS!!!
220 Tank build
http://www.aquariumforum.com/f15/sta...late-3253.html

Is a common mistake because tanks in the shop are even more overcrowded. The thing is fish don't stay in shop tanks for long, they usually do very large daily water changes etc., and when it comes down to it fish are cheaper than tank space so they can afford high death rates. Providing a healthy long term home for fish is different.

Meds usually weaken fish too. Overcrowding plus weak fish = fish deaths. I wouldn't treat for anything else so soon, I think it might just make the problem worse.

Try doing something about your stocking level. If your tank looks to empty try adding decor and easy plants, your fish will enjoy that too.

FYI, when I run the numbers I'm getting 53 US gallon tank.

100x50x40 = 200,000cm3

Answer: 200000 cm³ = 52.8344 gal(US Liq)
OR 52 gal(US Liq) and 6.67 pt (US Liq)

from here Cubic Centimeters to US Gallons (Liquid) conversion calculator

Fish dieing for "no reason" very well can be from an overstocked tank.

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100 Dirt + Stuff. To be Angel baby tank.
37 Planted. http://www.aquariumforum.com/f45/pla...nal-20774.html
29 Tall community tank. 5+ Years up and running.
15 Soon to be RCS tank.

Thanks for the correction

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Officially fishless until after the move....tune in later for details!

Easier: 200/4 = 50g = close enough for me.