Glofish died after 12 hours

[mt.everett]

I have a 10 gallon tank to which previously a few glofish have died so I reset up the tank. I have set up my tank with topfin glofish aquarium gravel, washed with very hot water to ensure no black dye comes off. I have a heater and a filter fit for my tank. I have an air stone and a few decorations which have been rinsed. I used nutrafin water conditioner and nutrafin cycle as per the instructions. My fish appeared fine swimming for the first few hours, I watched them for a while then when I went to bed they were okay. I woke up a few hours later, they were still fine and then 3 hours later (a total of 12 hours after I got them) I found them dead. I did acclimate them slowly and properly. Unsure what the issue is? Could it be the aquarium gravel or type of fish?

[Aiken Drum]

We suddenly have a lot of posts regarding glofish dying within a day.

The kind of things that are likely to kill fish in such a short time frame are.

Already sick fish.

Not acclimating properly.

Chlorine, ie no dechlorinator.

Low oxygen content, ie not enough surface agitation

Glofish are notoriously not hardy fish, so anything not quite right is more likely to kill them off. You havent been able to give us much clue as to what the problem is. Do you know your water parameters? How many fish are we talking about? Where did the fish come from? Did they have a long journey to your home?

[mt.everett]

The pH was slightly basic, just above 7.. I had plenty of water agitation and I tested it with the tetra strips many times. Safe levels of chlorine, nitrates and ammonia.

The first time I got glofish and they died briefly after I got 3.. this time i got 1 because I ddn’t want to kill off more fish, I would’ve added more if it had survived. They came from Petsmart this time, Petland last time. They were in the car for 15 minutes and straight into the acclimating process. Float the bag and add water slowly etc etc.

[mt.everett]

would getting mollies be any better? should i try another fish do you think?

[mt.everett]

i just double checked, the pH is 7.8.

[Aiken Drum]

At 7.8pH, ammonia is much more toxic than it is at lower pH levels. Thats around the point where ammonia starts to become a problem even at low concentrations. So you need to make absolutely sure your ammonia is low to zero.

Your pH is quite high, possibly much higher than the store water. So pH shock becomes more of a factor. Maybe a lengthier drip acclimatisation will help. On the plus side, a high pH makes cycling much easier.

In case you arent aware, your test kit measures total ammonia which is free ammonia + ammonium. Free ammonia is extremely toxic, ammonium much, much less so. As your pH rises the proportion of free ammonia to ammonium increases towards more ammonia and so what you measure with your test kit becomes more toxic.

Are mollys more hardy than glofish. Definitely.

[mt.everett]

i was wondering what would be making my ph so high?

[Aiken Drum]

What pH is your tap water?

Fish can acclimate to a wide range of pH. So i wouldnt go trying to adjust it with chemicals or anything. Just make sure you cycle the tank properly and the pH shouldnt be a problem.

If the pH in your tank is higher than your tapwater then something in the tank is raising it. Perhaps the substrate or any rocks?

If you want a more natural way of lowering pH, then driftwood in your aquascape will do this. Indian almond leaves scattered over the substrate also, as well as peat moss in the filter. Note that these will also release tannins and will stain the water, so you may need to do something about tannins if you dont like the look of them.