Does vinegar kill benificual bacteria

Hi, I have a 20 gallon tank and my younger brother dumped about half a cup of vinegar into it. We did a few water changes, probably will do more and the fish are OK, but I'm worried it killed the benificial bacteria and uncycled my tank. My tank is stocked with 2 khuli loaches, 3 dalmation mollies, 5 danios, one juvinile sunset gouriami and 2 sparkling gouriamis. It also has a plant. Any ideas what to do?

 

As far as I know, your BB should be fine. No guarantees though.

 

Vinegar shouldn’t kill your BB, but can definitely affect your pH. You should be fine now that you’ve changed the water, but what the heck would he do that for?

 

Ok so that much acid in a 20 gallon tank just plummeted your PH and that absolutely will effect the fish and ultimately your bacteria. Different nitrifying bacteria thrive at different PH levels so if you don't get it back to normal soon it can effect your cycle.

Change more water.

 

Vinegar shouldn’t kill your BB, but can definitely affect your pH. You should be fine now that you’ve changed the water, but what the heck would he do that for?

He has a disability, so he didn't really understand what he did, but I'm still confused myself. We've had this fishtank 12 years and he's rarely ever messed with it at all, let alone doing something like this.

Ok so that much acid in a 20 gallon tank just plummeted your PH and that absolutely will effect the fish and ultimately your bacteria. Different nitrifying bacteria thrive at different PH levels so if you don't get it back to normal soon it can effect your cycle.

Change more

Your probably right, I was scared to do a big water change (more than 50%) at first bc the shock of the new lower pH almost killed one of my khulis, and I was worried that the shock of going back right away might stress him out more to the point of death, so I've only done 2 smaller (around 40%) water changes. Now that he looks better, I'll probably do like a 60 or 70% water change today, and more evrey couple days over the next week. Do you think it is a good idea to buy something to help the cycle just in case the bacteria died, or just to monitor the ammonia levels and do more frequent water changes? I'm a beginner at fishkeeping and had difficulties in the past with cycling tanks, so I'm really worried bc I've experienced how bad and deadly an uncycled tank can be.

 

He has a disability, so he didn't really understand what he did, but I'm still confused myself. We've had this fishtank 12 years and he's rarely ever messed with it at all, let alone doing something like this.

Your probably right, I was scared to do a big water change (more than 50%) at first bc the shock of the new lower pH almost killed one of my khulis, and I was worried that the shock of going back right away might stress him out more to the point of death, so I've only done 2 smaller (around 40%) water changes. Now that he looks better, I'll probably do like a 60 or 70% water change today, and more evrey couple days over the next week. Do you think it is a good idea to buy something to help the cycle just in case the bacteria died, or just to monitor the ammonia levels and do more frequent water changes? I'm a beginner at fishkeeping and had difficulties in the past with cycling tanks, so I'm really worried bc I've experienced how bad and deadly an uncycled tank can be.

Large water changes will stress the fish a bit but they will get over it.
Large PH fluctuations will shock your fish and thats dangerous.