Tap Water Suddenly High Ph, Killed Most Of My Tetras, Don't Know What To Do Now

Firstly, I've read lots on how to lower pH in a tank. And I've read about dealing with high pH tap for new tanks. My problem is that my tap water went from ph7 to ph8.4, and my tank was already established at ph7ish. And I really need advice, because I have no idea what I'm going to do for my next water change!?

So tank history I guess. I've had this 25gal setup for 2 years... Freshwater, fake plants, gravel. It had a emerald Cory, a squeaker catfish, 7 bloodfin tetras and 2 nerite snails. My tap water came out pH 7 but VERY soft, pretty much no minerals. I used crushed coral in a netted bag in my filter to keep the tank's pH from plummeting. Was an ongoing battle.

Well this week, after a water change, my tetras started freaking out, darting and very stressed. At this point I have lost all the tertas except one when I tested the water I was shocked at the pH. I've NEVER had a problem with high pH, only low. Decided to check my tap and sure enough, it came out at 8.4 and not soft anymore. I immediately took the crushed coral out of my tank, but the damage was done. SO glad I didn't do my 6gal betta tank that week.

The tank has slowly come down to a 7.2 but I have no idea what to do now. I let a 5 gal bucket of tap water age 24hrs with prime in it, and the pH didn't change. (I tried at 48hrs too, with no change). I've read about tips to lower tank pH, but that won't help during a water change which will still cause pH shock. I've read fish can adapt to different pHs? But 8.4 seems pretty high for that, plus what happens if my tap changes again!? I'm really not sure how common that is? I thought about buying an small RO pump, this would change my water to neutral pH right? Does it make water soft too?

I'm so upset and frustrated and I really need advice. Thanks for any help. Sorry about the rambling.

 

Where do you live? Is this a change in your well water or municipal (city) water?
If it's municipal water, first call your water company and ask them what new process they're using to treat your water. That will tell you a lot about how you'll either need to adjust your water or acclimate your fish to the harder, more alkaline water. I'm a little confused. How did your tank gas out from 8.4 to 7.2 but a bucket of water stayed at 8.4 for 48 hours? You can try aging water for 24-48 hours without treating it with Prime. Maybe there's something in the prime that's stabilizing the pH. I didn't think so but that's just...weird.

 

Hello
You can use Neutral-Regulator that will help you to adjusts high or low pH to a neutral pH of 7 those adjustments has to be made it bucket and leave it seat for 24-48 hours. Do not try adjust PH in fish tank or use any chemicals.. RO water will help you for sure you might want to do more research how it works and how to remineralize water..

 

Welcome to Fishlore!

You say that it doesn't come out soft anymore. Can you provide the tank and tap readings so that we can see a better picture of what is going on?

I agree with Momgoose56 that a phone call might be a good idea. The city might have had to change to a different water source, or they may have chosen to make adjustments to the water, possibly to try to prevent it from corroding pipes. Whatever the case, it's best to get it from the horses mouth.

 

Thank you for the replies! Just what I thought I had a handle on water chemistry of fish tanks, I'm falling down rabbit holes again trying to figure things out

I called my local water department (Fresno, CA, USA - Calif Central Valley) and they were extremely unhelpful, the guy obviously just wanted to get rid of me :/ he kept repeating that pH7-8 is their target range, give or take 4-6 points. Gee thanks man. I pressed as to why the fluctuations happen and he just said that sometimes it's surface water sometimes it's ground water, that the water source changes. I asked if it was to do with minerals and he replies "well it's more complicated than just that." After circles of the same answers I finally gave up.

I tested my tank and tap today, unfortunately I don't write down old results, and I think I will start. I am using the API liquid test kit. Tap: pH 8.4, kh and gh both took three drops each so 53.7ppm on both if I'm reading the chart right. Nitrates 0 (checked just in case).

Tank right now: pH 7.4-7.6 (pH test showed 7.6, but when I did pH high range test it looked 7.4 but was also hard to tell...) Kh 3 drops at 53.7 and gh 6 drops at 107.4ppm.

As for my last post, sorry if I made that confusing. The fish tank didn't test at 8.4, I meant that the tap was at 8.4 when I unknowingly added it to tank, and the pH usually hovered at or just below pH7. I've always battled lower pH, hence crushed coral. The pH swung up to 7.2 I believe, although now it's testing at 7.4/7.6 and don't know if I tested wrongly the first time or something else is causing the change. Wow my head hurts...

My biggest conundrum is do I try and slowly change my tank to a pH8.4 tank or maybe use the Neutral regulator before water changes ... ? I've heard fish can adapt to a slow change in pH, but is there a limit to that? I'll definitely research more about remineralizing RO water in case I go that route. I have an aunt with well water that I'm taking my test kit to today. I visit weekly, and would not be opposed to trucking over jugs for water changes...

Should I add my crushed coral back since my kh is low???

 

How quickly did you refill the tank? Tap and tank parameters almost never match so I always do it slowly.

Don't get one of those cheap, small RO filters especially if you have chloramine.

 

Thank you for the replies! Just what I thought I had a handle on water chemistry of fish tanks, I'm falling down rabbit holes again trying to figure things out

I called my local water department (Fresno, CA, USA - Calif Central Valley) and they were extremely unhelpful, the guy obviously just wanted to get rid of me :/ he kept repeating that pH7-8 is their target range, give or take 4-6 points. Gee thanks man. I pressed as to why the fluctuations happen and he just said that sometimes it's surface water sometimes it's ground water, that the water source changes. I asked if it was to do with minerals and he replies "well it's more complicated than just that." After circles of the same answers I finally gave up.

I tested my tank and tap today, unfortunately I don't write down old results, and I think I will start. I am using the API liquid test kit. Tap: pH 8.4, kh and gh both took three drops each so 53.7ppm on both if I'm reading the chart right. Nitrates 0 (checked just in case).

Tank right now: pH 7.4-7.6 (pH test showed 7.6, but when I did pH high range test it looked 7.4 but was also hard to tell...) Kh 3 drops at 53.7 and gh 6 drops at 107.4ppm.

As for my last post, sorry if I made that confusing. The fish tank didn't test at 8.4, I meant that the tap was at 8.4 when I unknowingly added it to tank, and the pH usually hovered at or just below pH7. I've always battled lower pH, hence crushed coral. The pH swung up to 7.2 I believe, although now it's testing at 7.4/7.6 and don't know if I tested wrongly the first time or something else is causing the change. Wow my head hurts...

My biggest conundrum is do I try and slowly change my tank to a pH8.4 tank or maybe use the Neutral regulator before water changes ... ? I've heard fish can adapt to a slow change in pH, but is there a limit to that? I'll definitely research more about remineralizing RO water in case I go that route. I have an aunt with well water that I'm taking my test kit to today. I visit weekly, and would not be opposed to trucking over jugs for water changes...

Should I add my crushed coral back since my kh is low???

I would suggest to go ahead and put the crushed coral back into the tank to help buffer the KH, since both tank and tap are currently at 53.7ppm KH.

You say the tap water is also at 3dgh or 53.7ppm. So, what is happening is that due to this soft water source, the city is using something to boost pH so that it doesn't corrode the pipes, which it would do if they didn't. But this increase in pH isn't due to an increase in the buffering capacity as we are use to seeing in our fish tanks. They add something to the water that shift hydrogen ions into hydroxide ions, which increases pH. Momgoose56 may remember what is used in her water...but I can't remember the names right now and they may use something different in yours. But this allows them to obtain a higher pH than the water would typically have.

I would not strive to obtain the pH of the tap water because acid buffers within your tank will likely help to lower the pH of the tap water when given time, and he is correct in saying that all they at the treatment plant have to do is have pH in a range. So it will change periodically, and you will always be trying to obtain that new pH if you are tracking it. The main thing you want to do when doing water changes, is to add the water back in very slowly, which will help the fish adapt to any pH changes.

Also, the mineral content of the tap water to tank water is also quite a bit different. This too can cause fish problems if changes are made too rapidly. I find fish will react negatively to changes due to mineral concentrations just as severely as pH. So, it's another good reason to add water back in slowly.

Alternate water sources tend to be used at different times of year in many cities. There is often a spring and fall changing of water sources. Sometimes if turbidity is too much of an issue, or high levels of contamination from something that can not be sorted out in a timely fashion, a city may switch to an alternate water source at that time as well, if water resources will allow it.

Even your aunt's well could have different pH levels throughout the year depending on water levels, but I think we would be talking more minor shifts. But an increase in water supply or dry seasons, can change things.

 

So sad... I usually test my tap water before changes.

 

It's better to stabilize your pH at a higher level and let your fish acclimate to that than to try to hold your pH at a lower level with chemicals you have to add repeatedly. Crushed coral will increase your KH, maybe GH a little
It won't likely raise your pH over 7.6 but will stabilize it there and will keep it from dropping rapidly after you add it to the tank. Limestone chips will do that too but I'm not as familiar with how fast or effectively they work.
You'd put about 1 lb. crushed coral per 10 gallons total tank volume as part of your substrate or about 1 Cup per 30 gallons total tank volume in your filter overflow (in a mesh bag of course). The reason there's a difference in the amount is due to the amount of water circulation through the coral. The Calcium Carbonate in the coral stabilizes the water and keeps it from fluctuating wildly by releasing buffers (carbonate) automatically in response to acid.
If your tank is small enough just setting the water out overnight in a 5 gallon bucket may allow the pH to drop some itself before you add it to the tank.
Why don't you test that? Put some tap water in a glass container, test the pH, then let it set 10 or 12 hours and retest it. Then retest it again at 24 hours. See if the pH lowers.
It wouldn't be feasible to "age" water that way for a large tank but it would work for 20 - 30 gallon tank water changes.

 

It's better to stabilize your pH at a higher level and let your fish acclimate to that than to try to hold your pH at a lower level with chemicals you have to add repeatedly. Crushed coral will increase your KH, maybe GH a little
It won't likely raise your pH over 7.6 but will stabilize it there and will keep it from dropping rapidly after you add it to the tank. Limestone chips will do that too but I'm not as familiar with how fast or effectively they work.
You'd put about 1 lb. crushed coral per 10 gallons total tank volume as part of your substrate or about 1 Cup per 30 gallons total tank volume in your filter overflow (in a mesh bag of course). The reason there's a difference in the amount is due to the amount of water circulation through the coral. The Calcium Carbonate in the coral stabilizes the water and keeps it from fluctuating wildly by releasing buffers (carbonate) automatically in response to acid.
If your tank is small enough just setting the water out overnight in a 5 gallon bucket may allow the pH to drop some itself before you add it to the tank.
Why don't you test that? Put some tap water in a glass container, test the pH, then let it set 10 or 12 hours and retest it. Then retest it again at 24 hours. See if the pH lowers.
It wouldn't be feasible to "age" water that way for a large tank but it would work for 20 - 30 gallon tank water changes.

I don't think she is adding anything for pH.… another member supplied the pH 7.0 regulator link.....

We were discussing what the water treatment plant uses to increase pH. Isn't it you who also has softer water with a higher pH due to what the water treatment plant does?

Edit: Other than crushed coral that is....

 

I don't think she is adding anything for pH.… another member supplied the pH 7.0 regulator link.....

We were discussing what the water treatment plant uses to increase pH. Isn't it you who also has softer water with a higher pH due to what the water treatment plant does?

Edit: Other than crushed coral that is....

OH! Sorry, No actually, I have high KH, GH, and pH 8.2 drops to 7.6 in tank. Maybe it's Mattgirl?

 

OH! Sorry, No actually, I have high KH, GH, and pH 8.2 drops to 7.6 in tank. Maybe it's Mattgirl?

Lol. Or maybe JenC. I can't remember. I guess what exactly it is, is really not that important. Its...something. lol Thanks!

 

OH! Sorry, No actually, I have high KH, GH, and pH 8.2 drops to 7.6 in tank. Maybe it's Mattgirl?

I know! You are thinking of Soda or Lime ash that buffers without raising GH.

 

I know! You are thinking of Soda or Lime ash that buffers without raising GH.

And sodium hydroxide. Lol. I had to go looking for that post. I remembered it was hydroxide something or other! And yeah, you had also mentioned the soda ash. Thank you!

I'll link that discussion being as I went and found it.

https://www.fishlore.com/aquariumfishforum/threads/low-kh-and-gh-high-ph.400385/#post-4092827

 

Wow! Thank you for the replies!! I honestly had not heard of water harness changes being as problematic as ph swings. And thank you for the link, I will check that out. Things are at least making more sense, ty for the explanation toosie.

Okay ... So dumb newbie question.... When people say add water slowly, how slow is that? I usually used a python in the past, which although shower than dumping in a bucket, it's pretty fast.... But how slow should it be? Especially if I'm ooking at such a large difference in tap be tank parameters?

 

Wow! Thank you for the replies!! I honestly had not heard of water harness changes being as problematic as ph swings. And thank you for the link, I will check that out. Things are at least making more sense, ty for the explanation toosie.

Okay ... So dumb newbie question.... When people say add water slowly, how slow is that? I usually used a python in the past, which although shower than dumping in a bucket, it's pretty fast.... But how slow should it be? Especially if I'm ooking at such a large difference in tap be tank parameters?

If you have a buffer in the tank like crushed coral, you don't need to add water slowly. If you don't have a buffer, I'd suggest "aging" the water-letting the water sit in open buckets for 48 hours-before adding it to the tank. Typically the pH will 'self adjust' in that amount of time, back to the origins pre-treatment pH level.

 

If you have a buffer in the tank like crushed coral, you don't need to add water slowly. If you don't have a buffer, I'd suggest "aging" the water-letting the water sit in open buckets for 48 hours-before adding it to the tank. Typically the pH will 'self adjust' in that amount of time, back to the origins pre-treatment pH level.

I had crushed coral in a mesh bag in my filter, which I took out during the pH rise because I was worried it would make thinks worse. But will be putting that back in today to bring my buffer up. I tried aging the water, but didn't see any pH change even after 48 hrs

What is a good buffer range to prevent swings in pH during water changes??

 

I had crushed coral in a mesh bag in my filter, which I took out during the pH rise because I was worried it would make thinks worse. But will be putting that back in today to bring my budget up

Good deal! In the filter, you'll want about 1 cup CC per 30 gallons tank water. Switch the coral out for fresh rinsed coral every 2-3 months because with the high water flow, bacteria and other microbial growth will 'encapsulate' it, preventing the dissolution of the carbonates from the coral.

 

Okay ... So dumb newbie question.... When people say add water slowly, how slow is that? I usually used a python in the past, which although shower than dumping in a bucket, it's pretty fast.... But how slow should it be? Especially if I'm ooking at such a large difference in tap be tank parameters?

You can turn down the flow at the tap. It might take some experimenting to see how fast or slow you can do. The greater the difference between tank and tap water chemistry, the slower you should refill the tank. You can even refill in stages to give fish a little more time to adjust.

Typically the pH will 'self adjust' in that amount of time, back to the origins pre-treatment pH level.

I tried aging the water, but didn't see any pH change even after 48 hrs

I believe pH will only change when "aged", when CO2 is the cause for the change...so when CO2 either leaves or gets absorbed, and the gas in the water comes into equilibrium with the gas in the air, the pH will adjust accordingly. Other pH adjustments aren't affected unless or until an opposing buffer effects change.