Dying Guppy Please Help!

[Danio8]

Please help. One of my female guppies is dying. I just got her along with 4 other guppies, 1 male and 3 females. I just got another male today. All the other fish seem to be doing just fine. Please help, I don't want her to die.

1~What type of fish is afflicted? Female Elephant Ear Guppy. Half of her tail is gone, her head looks like it has been rubbed raw, and she is just lying at the bottom of the hospital tank.
2~What are your tank parameters ammonia=0, nitrites=0, nitrates=less than 5, temp=75 f, pH=8.2
3~ How large is the tank? How long has the tank been set up? 20 Gallons. The tank has been set up for about a month.
4~What type of filtration are you using? Marineland Penguin 200 BIO-Wheel Power Filter. Unknown Gph.
5~How many fish are in the tank? What kinds of fish are they and what are their current sizes? 6 Zebra Danios (all about 1.5 inches and purchased on May 10.) and 5 other guppies (2 males, 3 other females. All about 1 inch purchased on June 3.)
6~When is the last time you did a water change and vacuum the gravel? How often do you do this? How much water do you remove at a time? Water was changed today. I vacuum usually every week. About 25% of the water is changed each week.
7~How long have you had the fish? If the fish is new, how did you acclimate it/them? I have had my sick female for 1.5 days. I acclimated her by floating the bag for 45 minutes and then took a net and scooped her and the others out.
8~Have you added anything new to the tank--decor, new dechlorinator, new substrate, etc.? Nothing new since starting. (Besides fish)
9~What kind of food have you been feeding your fish, have you changed their diet recently? Aqueon Tropical Fish Flakes twice every day and freeze dried bloodworms twice every week. (The guppies have eaten one serving on bloodworms.)

 

[Danio8]

Another one of my female elephant ears is also just lying on the bottom of my tank. Her head does not look injured and her tail is intact. Both of these guppies were the smallest. Does anyone know what is happening to my guppies!?

 

[Aiken Drum]

Are you seeing any aggression towards your new fish, either from already in the tank or between your new fish?

How long where the new fish in transit between wherever you bought your fish and home? If it was a long journey waste could have built up in the bag before you got them home and be causing issues.

Maybe there is a water parameter difference between your tank water and the fish stores water. Perhaps a drip acclimatisation would help in future.

Maybe the fish where already sick before you got them. What is the condition of fish in the store? Are you seeing dead and dying fish there? Perhaps you should consider a couple of weeks quarantine in future before adding fish into your display tank.

You mention a hospital tank. I would look to treat with a broad spectrum anti-biotic medication in there with lots of water changes. What are conditions like in the hospital tank?

Not every fish you buy will survive long term. They are mass bred, often lots of interbreeding, poor genetics, often poor water conditions. New fish often come with built in health issues. A good quarantine process can help some of those fish get over any issues and weed out the ones that just arent going to make it before they go in your display tank.

 

[Danio8]

Thank you for your input. Sadly, both of the afflicted females didn't make it. The 3 other guppies that I got with the 2 sick females look like they are doing well. I will keep in mind what you have said in case any of my other fish fall ill. The new fish were in transit for just under an hour.