Ph crash causeing fish to flick??

[Andyskoi]

Hi i did a water change on my 50 gallon goldfish and koi tank a few days ago i never normally do more then around 30% but this time i did around 50% as i got carried away cleaning the gravel. The next day the water had a really strong smell of gas coming off it and the fish where flicking then siting on the bottom of the tank fins clamped. I done a water test and got the following readings

Kh 0
Gh 60
Ph 6.0
No2 0
No3 20

Is the ph to low and is that what is causing the strange behaviour? The tank has been running around 6 months,

Any advise would be great

Thank you

 

[Samzter]

Do you know what the ammonia is?

 

[Andyskoi]

It is 0.25 i have never managed to get it 0 on any of my tanks i have always put that down to the tap water, thanks

 

[jlk]

What are you testing with (liquid or strips)? What is your stocking? A ph of 6 or less and KH of 0 is a huge problem for goldfish. They do best in hard, alkaline high ph water.

I suspect your issues are combination of overstocking and lack of sufficient water changes/cleaning. Koi honestly do not belong in home aquaria unless you have a huge tank and this would explain why there is always ammonia present. Some more information will help!

 

[Andyskoi]

I use liquid for the ammonia and strips for the rest and there is 2 small koi 3" and 4" and 2 goldfish around 4", thanks

 

[Rivercats]

Your problem is with a ph of 6 your beneficial bacteria has stopped working hence the ammonia. With a Kh of 0 you have no buffers in the water to keep Ph up and stable. Koi and GF produce a ton of ammonia in the water and buffers (Kh) need to be high enough to contend with all of it. Koi and GF need a higher Ph and Kh.

What you need to do is add 1/2 teaspoon of baking soda dissolved in a cup of tank water into the tank and wait 2 hours. Test Kh. Your aiming for at least a Kh of 6 if not higher. After 2 hours and depending on the Kh reading repeat the procedure. Wait until the next day test the Kh and repeat the above process again as needed. Do this daily until your Kh is 6 or higher. Ph will raise as Kh does and it's Kh you need to monitor. Do not rush this process as raising the Kh too rapidly can cause a whole new set of problems.

Then you have to go to doing weekly minimum 50% WC's or even twice weekly WC's to keep buffers up (unless you have soft water which you need to test your tap Kh) and remove all the excess waste they produce. Another thing is you have to keep filters in these tanks cleaned much more often than you would in normal tropical fish tanks. I kept 4 large fancy GF in 55g tanks with a Fluval 406 canister and Wisper 70 HOB filter per tank. I had to clean the HOB weekly and the canister every 2-3 weeks due to the bioload of the 4 fish. Dirty filters raise nitrate levels. You have to be dedicated to keep GF IMO. Koi honestly shouldn't be kept in tanks. The only time I've kept koi in a tank is when we imported some small 5-6" fingerling Koi during the winter and couldn't put them in the pond due to temps. We kept them in a 220g tank with 2 huge FX5 filters running and 50% WC's weekly.

One other thing I strongly suggest is getting and using Montmorillonite Calcium Clay. It is very good for Koi health and also helps keep Kh up. You can find it under Koi or Pond supplies. It should be used weekly.

Once your Kh is raised and Ph rises above 6.5 your tank will actually go through a mini cycle as it will be starting from scratch recycling. Then you have to watch nitrites also and you will have to do WC's any time ammonia or nitrites raise above .25ppm.

 

[Andyskoi]

Thank you rivercats i will get started with that today. I tested my tap water and got the following readings

Gh 180
Kh 240
Ph 7
No2 0
No3 0
Ammonia 0.25

Thank you

 

[Rivercats]

You have a touch of ammonia in your tap what but not too high. Once you get your Kh and Ph up and the tank recycles then the water and BB in the tank will be able to easily process the small amount of ammonia in your tap water. But since you do have ammonia in your tap water it would be a good idea to periodically test it to be sure that amount hasn't risen to higher levels.

 

[Andyskoi]

Still no improvement in the kh or ph and now my goldfish has blood streaked fins and so does my shubunkin i have added half a teaspoon of bicarbonate soda yesterday and half today and done a 20% water change. Not sure what else i can do now or what has suddenly caused this but the fish are looking very sorry for themselves. I have read online that it should be 1 teaspoon for every 5 gallons is that wrong? Thanks

 

[Rivercats]

The problem is your not doing large WC's. 20% won't help and the red streaks are coming from the toxins (ammonia) in the water. Do what I said, a 70% WC wait a couple hours then another 50% WC. If needed even do a 3rd one 2 hours later. Then do a 50% WC everyday until you get a test kit.

Right now you need to do the WC's. And as for the baking soda you can't shock the already struggling fish by instantly raising the kh/ph to a high level from a very low one. The WC's will add buffers back into the water as well.

 

[Andyskoi]

One of my goldfish has just died this fish had dropsy around a year ago and looked like a pine cone and we where very lucky that she survived that but i think from that she had a low immune system and this latest problem with the ph has seen her off, just going to have to keep doing these 50% water changes everyday now and hope i dont lose the last 3 fish, if i do its the last goldfish and koi i get think i will just start another tropical tank

 

[Sharpchick]

The problem is the tank size for the fish you are trying to keep. That's one of the reasons we have jlk's sticky on the visual perspective of goldfish - why they need the large tanks.

Koi are not aquarium fish - unless the aquarium is several hundred gallons, and even at that, you can't have several koi living in there long term. You said you had two 4 inch goldfish, but you didn't say what kind - if they are comets, commons or shubunkins, you'd still have water quality problems with just the two of them, because again, those goldfish are pond fish.

I'm sorry to hear you lost a fish, but in your case, it's not the fish, it's the fishkeeper.