one of my 2 6” gar died suddenly, please help

[urip]

i have 2 gars with the same size (both are 6”) and ive been having them for 6 days. one of them suddenly died today. Its the one that keeps on eating frozen bloodworms. what happened to it?

i dont think its disease/ammonia bcs my other gar is still alive and i cleaned my tank 2 twice already.

 

[kno4te]

What are the tankmates? Check your water if you can. How often are you doing water changes? Feeding live food?

 

[urip]

What are the tankmates? Check your water if you can. How often are you doing water changes? Feeding live food?

tankmates are all small fishes like puffers and glowfish. In the past 2 days i been doing 2 30% water changes. And for the gar that died, he was eating live and a lot of bloodworms

 

[tlindsey]

been doing 2 30% water changes.

Welcome aboard
How long has your aquarium been up and running? Please describe how you clean the aquarium?

 

[urip]

How long has your aquarium been up and running? Please describe how you clean the aquarium?

its been 6 days.

i clean it with a gravel vac avoiding the gars leaving only 30% of the water. then i fill it back by flowing it thru my aquarium filter to ~80% capacity and then i pour my well water (the same well water from the store) to fill it to 100%. done this twice in the past couple days

 

[tlindsey]

its been 6 days.

i clean it with a gravel vac avoiding the gars leaving only 30% of the water. then i fill it back by flowing it thru my aquarium filter to ~80% capacity and then i pour my well water (the same well water from the store) to fill it to 100%. done this twice in the past couple days

Your lfs should have told you about how to cycle a aquarium.
It can take up to 6 weeks for a aquarium to cycle.
Do you have a freshwater aquarium test kit?

 

[Midwater]

its been 6 days.

Do you understand about the nitrogen cycle?

 

[urip]

Your lfs should have told you about how to cycle a aquarium.
It can take up to 6 weeks for a aquarium to cycle.
Do you have a freshwater aquarium test kit?

no i dont and the store doesnt sell it. ordering stuff will take days to arrive online, what should i do?

also i forgot to put this info, i use water from the stores established tank as my base 100%

 

[tlindsey]

use water from the stores established tank as my base 100%

Your filter needs to establish beneficial live bacteria which will take time to establish. There is really no beneficial bacteria in the aquarium water.

 

[urip]

Your filter needs to establish beneficial live bacteria which will take time to establish. There is really no beneficial bacteria in the aquarium water.

oh **** i just changed filters, is this the reason why?