Lowering kH and pH

[GaryE]

If you have a high enough organic content in your tank and don't water change your tank will eventually go acidic. All organic processes are based around acids. Acids are what break things down. What aquarists do is they think they need to water change their tanks; this is incorrect. If you have enough organic activity going on in your tank it will purify itself and it will be acid. The only thing you then need to do is top up. Which is what I'm doing.

This may work where you live, but don't present it as a general rule. People here live in a wide range of very different environments with very different water. I tried with my very well buffered water at my old home to take a few tanks acidic. It simply never happened.

Yes, it can, and I'm not discounting what has worked for you. But we're best to look at general approaches that should work across all environments. RO is a massive pain in the water butt. Storage, costs, etc. But you have to start with neutral water and build up. Removing minerals from a tank is murder. I had water out of limestone reservoirs, and friends have dealt with rock hard aquifers. Where does your water come from? @itiwhetu -didn't you say you start with rainwater on another thread?

I could reduce hardness by storing water in 20 gallon tubs half filled with soaked peat. But the water was very dark, and peat is not something we should be consuming at the rates we're consuming it.

 

[Alice B]

CO2. In large ponds (and I do mean several thousand gallons) I put in a couple of pounds of dry ice. The pH in these ponds is about 9.5 before I start, 8.5 afterward. Do not do dry ice in an aquarium, but a co2 generator should work

 

[Rocky998]

CO2. In large ponds (and I do mean several thousand gallons) I put in a couple of pounds of dry ice. The pH in these ponds is about 9.5 before I start, 8.5 afterward. Do not do dry ice in an aquarium, but a co2 generator should work

9.5!? That's really really high... Yikes

 

[Seb2502]

Awesome!! That will definitely make your tank 100% better.

So I’ve done some tests and I’ve determined a 2:1 ratio (2 being the Reverse osmosis water) is the way to go as it’s made the water have a gH of roughly 0, kH of 4.5 dKh (or 80ppm) and a pH of 6.4ish. So I’d say I’ve succeeded lol!

 

[TwoTankAmin]

As somebody who has an RO/DI unit and it is for Altum Angels. I start with neutral soft water but I need it closer to 6.0 and the TDS in the 60ppm range.

I will be curious as to how long the OP can keep the tank stable at the targetted parameters. I use a continuous monitor for TDS (or conductivity), pH and Temp. I batch my changing water in a a 20 gal can next to the tank so I can move the probes into the can to get the changing water targetted for the tank contitions at the time. I use an 11:9 mix and the changing water is normally in the 5.5 - 5.7 range when it goes in.

Finaally, I have droped the pH in that tank by 1.0 in under 5 minutes on a few occasions and the fish were perfectly fine. I learned this was safe when I watched the seller of my fisrt angels do this but the change was 1.1. Fish are way more sensitive to conductivity/TDS changes (or GH) than to pH changes.

I do stained water for the angels so I cannot use colormetric test kits. Stained water does not play nocely with these. So I use digital testing. Also, when I brought in freshly imported Altums I had the tank at pH 4.2 and the TDS between 20 and 30 ppm. I spent about 6 months bringing the tank up to 6.0 and 60-70 ppm.

You cannot accilmate fish to really changed conditions in a matter of hours or even a few days. The internal physiological changes take 1 -2 weeks to happen.

 

[Seb2502]

As somebody who has an RO/DI unit and it is for Altum Angels. I start with neutral soft water but I need it closer to 6.0 and the TDS in the 60ppm range.

I will be curious as to how long the OP can keep the tank stable at the targetted parameters. I use a continuous monitor for TDS (or conductivity), pH and Temp. I batch my changing water in a a 20 gal can next to the tank so I can move the probes into the can to get the changing water targetted for the tank contitions at the time. I use an 11:9 mix and the changing water is normally in the 5.5 - 5.7 range when it goes in.

Finaally, I have droped the pH in that tank by 1.0 in under 5 minutes on a few occasions and the fish were perfectly fine. I learned this was safe when I watched the seller of my fisrt angels do this but the change was 1.1. Fish are way more sensitive to conductivity/TDS changes (or GH) than to pH changes.

I do stained water for the angels so I cannot use colormetric test kits. Stained water does not play nocely with these. So I use digital testing. Also, when I brought in freshly imported Altums I had the tank at pH 4.2 and the TDS between 20 and 30 ppm. I spent about 6 months bringing the tank up to 6.0 and 60-70 ppm.

You cannot accilmate fish to really changed conditions in a matter of hours or even a few days. The internal physiological changes take 1 -2 weeks to happen.

I’m going to restart my 20 gallon and have it at the desired parameters for quite a while before adding any fish that way I can ensure it’ll be stable. I’m also going to have an old cycled filter in the tank so cycling won’t be much of an issue

 

[Back in the fold]

In my experience hardness can be manipulated with R/O or rainwater but pH is a whole other animal. It always wants to stay the same. You can buffer to an acid reading with things in the tank like driftwood, peat pellets, leaves and neutral substrate materials but as soon as you do a water change with your alkaline tap water you are right back at square one.

 

[Seb2502]

In my experience hardness can be manipulated with R/O or rainwater but pH is a whole other animal. It always wants to stay the same. You can buffer to an acid reading with things in the tank like driftwood, peat pellets, leaves and neutral substrate materials but as soon as you do a water change with your alkaline tap water you are right back at square one.

My pH was also affected by the R/O water. But yes I am going to have driftwood and catalpa leaves to help

 

[Alice B]

9.5!? That's really really high... Yikes

Gypsum in the water supply. Water your garden with it, the garden dies. Ph down, acid buffer, this stuff is a joke to that water. CO2 works, dry ice is Co2. But dosage is critical. I can throw 10 pounds in a 5000 gallon pond and not kill the fish, but half a pound in 300 gallons I had one fish die.

 

[Rocky998]

Gypsum in the water supply. Water your garden with it, the garden dies. Ph down, acid buffer, this stuff is a joke to that water. CO2 works, dry ice is Co2. But dosage is critical. I can throw 10 pounds in a 5000 gallon pond and not kill the fish, but half a pound in 300 gallons I had one fish die.

I guess I don't have the worst water afterall

 

[StevenF]

Gypsum in the water supply. Water your garden with it, the garden dies. Ph down, acid buffer, this stuff is a joke to that water. CO2 works, dry ice is Co2. But dosage is critical. I can throw 10 pounds in a 5000 gallon pond and not kill the fish, but half a pound in 300 gallons I had one fish die.

Gypsum is calcium sulfate, I use it in my tank and it will not put the PH up. I have also used calcium chloride and magneisum sulfate to remineralize my RO water. They will not push the PH up. Same for calcium carbonate and magnesium carbonate.

Typically water utilities push the PH up to minimize pipe corrosion. Fort Worth is doing that according to the report and is also has removed most of the lead pipes they have found (very good) but They typically don't push PH to 9. The Fort Worth water quality report dosn't say what they add to the water bu it says the PH is 8.2 to 8.4. Typically sodium bicarbonate is added to push the ph up in tap water but the report shows a sodium level too low to low for it to be the problem. Potassium bicarbonate could do it but they don't list potassium. Are you measuring the PH with lights on? When the light is on plants and algae will consume carbonate ions creating Calcium hydroxide or sodium hydroxide which will push the PH UP. I have gotten my PH up to 9 with light alone. But when the lights turn off the pH drops back to normal (in my case 7). You might want to check the PH first thing in the morning and before the lights turn on to see if the lights are causing your high PH. I have not sen any effect of light induced high PH on my fish or shrmp.

The water quality report doesn'explain why the water kills your plants. Perhaps too much chlorine?? The listed sodium levels are also too low tohave any effect on plants.

 

[Alice B]

This is Rhome city water, several years ago, the pond owner has passed on and I no longer visit this pond. I heard from an old farmer that the problem with the water killing his plants was gypsum. Fort Worth water is good. I typically see problems on rural Texas water supplies. Using test strips the KH will be high but the GH will be zero if the pond is going to be a problem. Because in ground plants may die, but pond plants don't last a week unless planted in soil, and if I want to remedy the water, in addition to burning off the pH, I put a stocking with some egg shells in the filter. Egg shells supply whatever the water is missing. I realize this isn't scientific, but I've been keeping ponds for other people about 23 years and the first time I ran across this water was in Alvord, TX in 2005

 

[StevenF]

Well no water quality report for Rhome. A Gh of zero and a high KH indicates they my be using a water softener to reduce GH. Water softeners use salt to reduce GH and but add sodium bicarbonate to the water. Water softened this way in my opinions not compatable with fish.. The GH test detects calcium and magnesium in the water. Both are needed by plants. Egg shells are mostly calcium carbonate. In addition to what you are doing now you might want to supplement your water with magnesium. carbonate. YOU can buy it online or at some health food stores as well as calcium carbonate. Normally these don't dissolve in high PH water but you are using a PH down product that probably helps it dissolve and increase GH. Plants prefer 3 parts calcium to one part magneisum. but the mix doesn't have to be precise. You can buy GH boosters but they typically add potassium. additional potassium with the sodium you now have I would not recommend using a commercial GH booster unless you can find one without potassium.

 

[Alice B]

no water quality report for Rhome, Bethesda water in Burleson, Alvord. I test water supply on arrival on these rural ponds. CO2 - dry ice for ponds is fine, I don't service aquariums anymore and thank goodness I don't have that water here. To supplement these, because working in the dark, in addition to eggshells, I've been putting in a handful of epsom salts (magnesium sulfate), and I think potash, which I am guessing might not be the best idea. Also one piece of limestone in a known location adds a lot of calcium, but in our sun it grows a lot of algae too, so if I put a small piece in a pond it is usually in the roots of a potted water lily. Thank you for sorting out the science. I've been flying with limited visibility for a while.

 

[Divinityinlove]

If you have a high enough organic content in your tank and don't water change your tank will eventually go acidic. All organic processes are based around acids. Acids are what break things down. What aquarists do is they think they need to water change their tanks; this is incorrect. If you have enough organic activity going on in your tank it will purify itself and it will be acid. The only thing you then need to do is top up. Which is what I'm doing.

If reducing water changes, then how to keep nitrates under control? Should I just dose prime and stability from seachem weekly and hope the cycle improves? Cut down water changes from weekly to monthly?