Fish dying. Help?

scotty703

It all started about a week ago. I noticed a white coating ( like velvet) on my angelfish and they where breating heavy and then they started dying off one by one. About 2 weeks ago, I bought 2 new Koi Angelfish, some plants, 1 Neon Blue Dwarf Gourami and a Sailfin Molly. Them four fish died first and then my other angelfish stared to die. About one every two days. I have tried raising the temp., adding salt, using copper safe, two treatments of Furan-2(anti-parasitic med.) and tonight I'm trying clout. I also did 25% water change with each treatment. Does anybody have any suggestions?

Ammonia 0.25 ppm after first treatment of med.
Nitrate 160 ppm
Nitrite always 0
PH always around 7.2
GH 300ppm very hard
KH 180ppm

55 Gal. Freshwater Under Ground Filter(power heads), Old Hang-On Filter with Floss (Have XP2 FilStar Canister Filter on order, but afraid to put on this tank until I get it cleared up!)

2 Koi Angels (Bought 2 weeks ago and died first)
3 Sailfin Molly (Bought one 2 weeks ago and died first) 2 still alive
2 Silver angelfish (died)
2 Black Angel fish still alive
2 marble angelfish one died
3 cory catfish all alive
2 Neon Blue Dwarf Gourami the one I bought 2 weeks ago died

Lupin

Scotty, you're adding meds unnecessarily and possibly mixing them which is quite dangerous.
Before using another med, try to remove the previous treatment using activated carbon.
The white coating sounds like they are producing excessive mucous membrane more than velvet.

Pls test your tapwater for nitrates. 160 ppm is quite high and you'll need several fast-growing plants like elodeas and duckweeds to consume the nitrates and more water changes to help with.

The reason why your ammonia is spiking is you may have killed your beneficial bacteria by dosing several meds which can harm the bacteria and the addition of decomposing bodies of your fish.
For that, do more water changes but you must also test your tapwater for nitrates.

Next time, you should correct the water quality first before treating your fish. It may not be disease that struck them but your water quality.
Water quality is second to stress for being inducers of poor health conditions.

bettababy

I want to start out by warning against medicating a tank while there is ANY ammonia or nitrite present. Medications are meant to work in good water quality conditions, and can have an adverse effect when there is any ammonia or nitrite or nitrate about 60.
The best thing to do right now is to listen to the mod, get some fresh carbon into the tank and soak out the medications over the next 48 hrs, along with a 25% water exchange.
How large are the angelfish? 55 gallons isn't enough to raise more than 1 angelfish to full grown. Angels top out at about 8 inches in diameter each, and as they get older they get more aggressive.
I never advise angels in a 55 long term, and never more than 2 - 3 of them short term for these reasons.
From the looks of your water quality, nitrate levels are up off the chart, and this is probably causing a large part of your problem. Nitrates that are too high for too long are also toxic.
How often do you do water exchanges? How much at a time? How often do you feed the fish? How often do you gravel vac and change carbon in your filter? The more info you can give us about your tank the easier it would be to help you.
For immediate advice, get the meds out, get new water stats posted, and DON'T BUY ANY MORE FISH for this tank until you have fixed the current issues. Buying more now will only make the problems worse and make it harder to define exactly what is causing it all.
If you desire to keep that many angelfish, I'd say now is a good time to start shopping for a tank of over 125 gallons, even if the fish start out small. They will grow into it quickly.
I'll watch this post and help as much as I can.
Good Luck!
bettababy