15g Column Tank Problems?

so I've had my tank for almost 1 year my cory cats are doing phenomenal but if I add any other fish they die after a week. I've tested my tank multiple times and everything comes back beautifully. i'm starting to think that maybe i'm not getting enough air flow to my tank so I added a bubble stone. all of a sudden after 1 month of having the bubble stone I got a huge algae bloom and I can't figure out what's causing this and my other fish to die

current stocking is
2 panda cories
1 albino cory
1 peppered cory
all of these fish have been in the tank for a year

ive lost 6 panda platies
a bubble bee platy
2 oto cats

starting to think I should change the filter.
i've been looking at the fluval aquaclear 30
i'm just not sure if that's what I should get.
I guess i'm asking for recommendations on how to stop killing fish


also I started with live plants but I wasn't able to keep them alive due to the awful light that comes with it and I haven't looked into doing deep penetrating lights yet

attached is a photo of my tank

 

Cory cats can live in water lower in oxygen than some fish because they occasionally zip to the surface and swallow a gulp of air. They extract it through their gut. Oxygen absorption only occurs at the surface so the water needs to be circulated to the bottom such as circulation caused by rising bubbles. You also need to do more water if you're getting algae spikes...maybe too much nitrate.

so I've had my tank for almost 1 year my cory cats are doing phenomenal but if I add any other fish they die after a week. I've tested my tank multiple times and everything comes back beautifully. i'm starting to think that maybe i'm not getting enough air flow to my tank so I added a bubble stone. all of a sudden after 1 month of having the bubble stone I got a huge algae bloom and I can't figure out what's causing this and my other fish to die

current stocking is
2 panda cories
1 albino cory
1 peppered cory
all of these fish have been in the tank for a year

ive lost 6 panda platies
a bubble bee platy
2 oto cats

starting to think I should change the filter.
i've been looking at the fluval aquaclear 30
i'm just not sure if that's what I should get.
I guess i'm asking for recommendations on how to stop killing fish


also I started with live plants but I wasn't able to keep them alive due to the awful light that comes with it and I haven't looked into doing deep penetrating lights yet

attached is a photo of my tankView attachment 436034

 

Cory cats can live in water lower in oxygen than some fish because they occasionally zip to the surface and swallow a gulp of air. They extract it through their gut. Oxygen absorption only occurs at the surface so the water needs to be circulated to the bottom such as circulation caused by rising bubbles. You also need to do more water if you're getting algae spikes...maybe too much nitrate.

I have very little nitrate in my tank. I honestly just don't understand. and I have a huge bubble stone in there now its just not shown in the photo. I added because I was told that's often what happens in the column tanks but its still not helping.

 

I have very little nitrate in my tank. I honestly just don't understand. and I have a huge bubble stone in there now its just not shown in the photo. I added because I was told that's often what happens in the column tanks but its still not helping.

is it hooked up to an air pump? I don't see any bubbles in the picture.

 

is it hooked up to an air pump? I don't see any bubbles in the picture.

It is not in the tank in the photo the photo was taken before the bubble stone was placed in(which is why I said it is not shown in this photo) yes its hooked up to an air pump

 

Did the fish die with any symptoms of a disease? It could have been where you bought them from.

 

Did the fish die with any symptoms of a disease? It could have been where you bought them from.

bought them from multiple different places and we had ick at one time but we treated and got rid of it. all fish that showed symptoms went in my hospital tank. and were free of symptoms before returning

 

Because we have to ask... and you clearly have an answer since you say your nitrates are low - can you share the results of your most recent water testing (ammonia, Nitrite & nitrate)? You have lost a lot of fish, that must be really frustrating. I don’t have any amazing ideas at the moment, but maybe your water parameters will give us something to work with?

 

One more thing to consider is that some fish are affected by ich a little less because of their resistance and cories are one of those species. You may hav cleared the ich from fish in a hospital tank, but their could be just enough ich living on your cories that are not causing them problems, but still able to infect other fish...just a speculation

Because we have to ask... and you clearly have an answer since you say your nitrates are low - can you share the results of your most recent water testing (ammonia, Nitrite & nitrate)? You have lost a lot of fish, that must be really frustrating. I don’t have any amazing ideas at the moment, but maybe your water parameters will give us something to work with?

 

Because we have to ask... and you clearly have an answer since you say your nitrates are low - can you share the results of your most recent water testing (ammonia, Nitrite & nitrate)? You have lost a lot of fish, that must be really frustrating. I don’t have any amazing ideas at the moment, but maybe your water parameters will give us something to work with?

I'm actually on vacation atm I should be back Wednesday and can give you my water parameters then

One more thing to consider is that some fish are affected by ich a little less because of their resistance and cories are one of those species. You may hav cleared the ich from fish in a hospital tank, but their could be just enough ich living on your cories that are not causing them problems, but still able to infect other fish...just a speculation

my fish are pretty and clear. ive thought that too but ive looked them over and they look super clean