Water Quality Problems

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.

cherisec

Aquarium Advice Apprentice
Joined
Jul 3, 2019
Messages
17
Location
Keelung, Taiwan
Good day, I have a 18 gallon tank with 4 guppies, 1 platy (I had 5 but the others died, they slowly started turning a whitish pink), 1 plec (I know a 18 gallon tank is too small, and I'm buying a bigger tank in January) and a snail and recently I've been struggling with a pH of less than 6.2. all my other levels such as nitrates, ammonia, chlorine, carbonates, and hardness are within accepted levels - I use test strips to test water quality. So I bought an alkaline stabilizer which says it will bring acidic water up to pH 7 or at least increase it. It's been two days since I added stabilizer and now the pH is increasing to accepted levels, but the carbonates are increasing beyond accepted levels. What should I do to bring down the carbonate level please?
 
Last edited:
Stop using the buffers. That's why your carbonates are rising and that's how the stabilizers adjust the pH . There are numerous fish species that live well in water with a pH under 6.2 so look into keeping those species vs trying to constantly needing to adjust your water. In low pH water, nitrification is very slow and under 5.0, it even stops. Toxic Ammonia in water under 6.8 pH is naturally converted to non toxic ammonium so no need to be concerned about the ammonia level. If you do routine water changes, you will prevent any nitrites or nitrates ( if present) from getting too high or to a toxic level. In fact, these things get more toxic in alkaline water. What's going to happen is as the fish or life is in the tank, they will be slowly absorbing the carbonates and once they have used them up, the pH will once again begin to fall. You can regulate this through your water changes but if your replacement water is also low in pH, your water will obviously be soft ( low GH), low in KH ( carbonate hardness) and low pH. If your replacement water is very alkaline with a higher KH and GH, you can control the pH in your tank water by doing more frequent water changes. To bring them down now with the stabilizer present, If you have low GH & low KH source water, do a water change. (y)

Hope this helps.
 
As Andy says, the stabiliser increases the pH by adding carbonate hardness (KH) to the water. As one goes up, so does the other. There isn't a way of increasing one without the other also increasing.

KH is a buffer that absorbs acids and stabilises the pH at a higher level.

Out of interest, what has your pH and KH increased to? What are you reading that says the KH is above "accepted" levels? Livebearer fish are generally hard water fish, and do well in higher levels of pH, KH and GH.

Trying to adjust the water parameters from what they naturally occur at in your aquarium almost always ends up doing more harm than good as you create parameter swings in the water, and the goal is to keep things steady. Keeping fish thar suit your water is almost always going to be more sucessful than trying to chemically force water to parameters to be something it doesn't want to be.

There are alternatives to buffering chemicals to raise pH, but these will similarly also raise KH and GH. Adding some crushed coral into your filtration or adding some cuttlefish bone into your aquascape is a source of calcium carbonate and will increase pH too.
 
Stop using the buffers. That's why your carbonates are rising and that's how the stabilizers adjust the pH . There are numerous fish species that live well in water with a pH under 6.2 so look into keeping those species vs trying to constantly needing to adjust your water. In low pH water, nitrification is very slow and under 5.0, it even stops. Toxic Ammonia in water under 6.8 pH is naturally converted to non toxic ammonium so no need to be concerned about the ammonia level. If you do routine water changes, you will prevent any nitrites or nitrates ( if present) from getting too high or to a toxic level. In fact, these things get more toxic in alkaline water. What's going to happen is as the fish or life is in the tank, they will be slowly absorbing the carbonates and once they have used them up, the pH will once again begin to fall. You can regulate this through your water changes but if your replacement water is also low in pH, your water will obviously be soft ( low GH), low in KH ( carbonate hardness) and low pH. If your replacement water is very alkaline with a higher KH and GH, you can control the pH in your tank water by doing more frequent water changes. To bring them down now with the stabilizer present, If you have low GH & low KH source water, do a water change. (y)

Hope this helps.
I
Stop using the buffers. That's why your carbonates are rising and that's how the stabilizers adjust the pH . There are numerous fish species that live well in water with a pH under 6.2 so look into keeping those species vs trying to constantly needing to adjust your water. In low pH water, nitrification is very slow and under 5.0, it even stops. Toxic Ammonia in water under 6.8 pH is naturally converted to non toxic ammonium so no need to be concerned about the ammonia level. If you do routine water changes, you will prevent any nitrites or nitrates ( if present) from getting too high or to a toxic level. In fact, these things get more toxic in alkaline water. What's going to happen is as the fish or life is in the tank, they will be slowly absorbing the carbonates and once they have used them up, the pH will once again begin to fall. You can regulate this through your water changes but if your replacement water is also low in pH, your water will obviously be soft ( low GH), low in KH ( carbonate hardness) and low pH. If your replacement water is very alkaline with a higher KH and GH, you can control the pH in your tank water by doing more frequent water changes. To bring them down now with the stabilizer present, If you have low GH & low KH source water, do a water change. (y)

Hope this helps.
Thank you for the advice. I'll do more research and see if there are any types of fish that like low pH available in my area. I also failed to notice that my test strips have expired so I've ordered new ones. Then I can check what is really going on in the tank
 
As Andy says, the stabiliser increases the pH by adding carbonate hardness (KH) to the water. As one goes up, so does the other. There isn't a way of increasing one without the other also increasing.

KH is a buffer that absorbs acids and stabilises the pH at a higher level.

Out of interest, what has your pH and KH increased to? What are you reading that says the KH is above "accepted" levels? Livebearer fish are generally hard water fish, and do well in higher levels of pH, KH and GH.

Trying to adjust the water parameters from what they naturally occur at in your aquarium almost always ends up doing more harm than good as you create parameter swings in the water, and the goal is to keep things steady. Keeping fish thar suit your water is almost always going to be more sucessful than trying to chemically force water to parameters to be something it doesn't want to be.

There are alternatives to buffering chemicals to raise pH, but these will similarly also raise KH and GH. Adding some crushed coral into your filtration or adding some cuttlefish bone into your aquascape is a source of calcium carbonate and will increase pH too.
My pH increased to somewhere between 6.4 and 6.8 and GH increased to more than 150mg/L. Took it from the color chart on the test strip bottle. But as I replied to Andy, I only saw now that the strips expired so I've ordered new ones. Also thinking of ordering the single pH and nitrate test kits for better readings. Thank you for your advice, it's appreciated.
 
GH of 150ppm is fine for guppies, but your query related to carbonate hardness (KH).

What has the KH increased to?
 
Back
Top Bottom