Help neon tetras died within 12 hours

[Clentipo]

Yesterday I bought 10 Neon tetras from a local pet store. I brought them home and let them sit in the bag in the tank for about 45 minutes while i did some maintenance and readjusting to the planted tank they would be entering. Its a 10 gallon tank with moderate plants, gravel bottom, a 20 gallon aqearian filter with biofilter and bio scrubber. Heated at 78 degrees. This tank also includes a male butterfly betta, 3 glo tetras and a glass tetra, with 2 nerite snails to help with maintenance. This tank also includes a marineland maxi jet 900 power head. Its being used as a pump and has the water flow directed up and into the corner of the tanks towards the filter. Its more to create a top water circulation rather than a current. The bottom of the tank is pretty calm.

This tank is about 3 weeks old. Since its cycled with fish I do a 25% water change daily and I use prime to condition and treat the water and I use ph down as my tap water runs at about 8, I keep it pretty steady between 7 and 7.2 ph.

I then transferred the tetras to a bucket slowly adding a cup of tank water every 5 minutes for 30 minutes. I then netted them and put them in the tank. They did fine for quite a while. They grouped up with the glo tetras and glass tetra and were having a blast. About 7 hours later I noticed the smallest neon tetra at the top of the tank gasping for air. I immediately grabbed my spare one gallon tank, put warm treated water in it and put an air pump in it and moved him to it. Less than 30 minutes later he was dead. I then think its ammonia spike. I do a test at it was at about 2ppm so i then do a 50% water change and and add a double dose of Prime to detoxify anything in the tank.

This morning i wake up and four more have died. I then remove them from the tank and put them in my other 10 gallon tank that is more established. Its been up for about 2 months but contains no real plants. The fish seemed to act better in the other tank but then 3 more died. Checked the ammonia and none in this tank. I still treated it with prime anyhow and put in a half tsp of aquarium salt. So now im down to 2 neon tetras and at this point they seem to be doing pretty well. Any advice on what happened?

 

[Delapool]

Hi, welcome to the forum

My experience with neons and from reading is that they will do better in a mature tank that is 3 to 6 months old and get good size ones.

 

[Clentipo]

Thank you. The two remaining tetras are doing much better. They are swimming around the tank together and eating. There seems to be no issues. Now I just feel bad because I know they are achooling fish and its just them in there. And you are right, the two that are left were the biggest neons in the group. Ill give it another month or so and get some more. I really want them in my planted tank but its still a fairly new tank.

 

[Delapool]

I confess I love the colours of them but find them so finicky to keep

 

[jessipanda]

I have cycled a 10g with neons, and still have 4 of the 5 I started with over a year ago. The only reason I have 4 is because a couple weeks ago I finally put the 5th one down after several months of it having some sort of issue that seemed to have been cancer. The remaining 4 have been in a 55 with cardinals and rummynose since November. I haven't lost any other tetras and my 55g was started (after being cycled) with 10 cardinals. There are 29 tetras in this tank, as well as a couple other fish.

From my experience, tetras don't necessarily need a mature tank....they need proper conditions. Meaning no ammonia, no nitrite, low nitrates, and a steady pH and temp. Just like all other fish really.

From what you've stated, you didn't really provide them with any of that. Floating fish in a bag for 45 mins is a very long time for ammonia to build up. Additionally, your 10g seems extremely over stocked with the tetras. With just the betta, 3 glo tetras, and the glass tetra, that tank is at it's maximum. To be able to add 10 neons to it, you would need at least a 15g sump running for the tank.

You stated that when the 1st neon started gasping, you tested your tank for ammonia and had a 2ppm reading. Yet you only did a 50% water change? That left 1ppm in the tank which is still lethal. Prime is supposed to bind ammonia for up to 24 hours, which should ideally make the water safe for fish and many people on this forum swear by it--myself included. However, you still should have done a larger water change at that point then added the prime as the ammonia building up in the tank was rapid. Honestly, with the number of fish you added so quickly and how young the tank is, I'm surprised any lived at all.

I'm sorry if I'm coming off rude... That isn't my intention at all. I'm just stating my opinion on the matter. My advice would be to not add any additional fish to your tank and next time you get fish, don't float them for longer than 15 mins in the bag. Also, when I buy fish, I have to drive at least 30 mins home with them in a bag, so I bring my own bottle of prime and add it to the bag before they tie it off. Helps loads!

Sorry for your losses. Hope it goes better next time. Tetras are my favs

 

[Clentipo]

From the pet store to my house is about a 2 minute drive. The tank has now been upgraded to a 20H. I've also updated the filter to a 30 gallon power filter and I've now added twice as many plants. And I agree the parameters in the tank weren't the best, however I placed them in my more established tank and they still continued to die off. I went to the pet store the next day and all of their neon tetras were gone. Which told me something was fishy.

I still have one neon tetra that is doing really well out of the bunch. He is now alone in a 10g with a single betta and 1 nerite snail. I've decided even though neon sign are gorgeous that I won't be trying my hand at them for a while.

I'm currently cycling another 10 gallon I have and once I feel it's ready, I may put a school in there.

 

[jessipanda]

Once they were exposed to that much ammonia, it was probably already too late so moving them only caused more stress in stressed fish. However, if all the ones at the store died off that quickly, they were probably doomed anyway. Hope they didn't pass anything on to your other fish. If you don't quarantine fish already, you should consider keeping a spare tank just for that. I run an extra sponge filter in my 55 and have a spare 10g just for a quarantine and hospital tank. I fill it up, add prime and the sponge filter, and run it for at least 24 hours with a spare heater before I pick up any new fish. Any new fish spend their first 3-4 weeks with us in it. And any sick fish go in it until healthy/expired. Haven't had to use it as a hospital tank though.

 

[Clentipo]

As soon as I realized the fish were all gone at the pet store. I removed my bio filters and used a treat all just as a precaution. Sadly I have had to use a hospital tank. I received a sick betta from Walmart. It spent a week in the hospital tank and was treated. He's now doing excellent.