Cheap Way To Lower pH

clayt101

Registered Abuser
I have a 125 gallon planted and am having problems. It mainly has fancy plecos and discus.

I set up a CO2 injector, using a timer...was working fine until one day it went crazy. I decided to get a pH monitor for it so that it could not go overboard again. For the first time I decided to measure my pH, its nearly 8 out of the tap.

Although my discus do fine in this, I figured the CO2 injection would cause the pH to go up more...which may be pushing it.

I bought some pH lowereing product, and I think it will take nearly the entire bottle ($9) to lower the pH to around 7. This will not work in the long run as I change 50% of the water each week.

So, I assume that there must be a safe, cheap way to lower pH...any advice?

Or am I okay with the pH at nearly 8, and running CO2? If this is the case, what should I set the pH cut off level at for the CO2 injector (this is also a question if I lower the pH to 7)?

Thanks
 
Well, after further review, I now realize it will take 2 bottles of the pH lowerer to get the whole aquarium to a pH of 7 and 1 bottle per week to maintain that level.
 
well co2 will not increase your ph. if anything it has the ability to lower it...

a ph of 8 is fine unless your fish are not fine. stable is better, than irratic changes in ph.

though if you still want to lower it. peat will be your best bet.
 
I guess I got things turned around. Okay, what pH level would you recomend for shutting off the CO2 (assuming the starting pH is 7.8)? My main concern is lack of oxygen going to the fish (this happened once when my valve opened up a little bit by itself).

Thanks
 
Clayt101,

CO2 with a controller, like you have, is the best way to lower and maintain a stable pH. If you’re having trouble it seems like something is missing in your system. First off, are you using a reactor? If not you may just be wasting the gas and exhausting it thru the water and into the atmosphere. What is the pH in your tank? You mention that it is 8 out of the tap, but that seems very high for Discus, they thrive down in the 6.6 range.

What do you mean that your CO2 injector “went crazy”? Did it dump all the gas into the tank? This can happen when the volume/pressure in the gas cylinder gets low and the regulator malfunctions. Hypoxia of the fish from too much CO2 isn’t about pH but rather the ppm of CO2 in the water and it is not easy to do and usually accompanies a crash in pH.

Here is my suggestion, read around this sight and others to get the chart and instruction on how to estimate your ppm of CO2 using pH and carbonate hardness. Then, if your levels are ok add more CO2 till you get the pH you want. This assumes other factors of the tanks water chemistry are fine, such as, no ammonia and adequate oxygen.

I would not recommend the pH reducers because there are many kinds and some will actually remove or cause certain nutrients to be unavailable for your plants. Plus they can make the water chemistry more unfavorable for your fish then higher CO2 levels.

As an example, I use to run a 45g with DIY Co2 thru a reactor and would get CO2 as high as 30ppm with no adverse affects to my fish. My tap water was in the high sevens but it was lowered down to 6.6 easy. Of course, your water chemistry and buffering will cause different results but lowering and controlling your pH with CO2 should be easier. Have fun and enjoy the hobby.
 
If your goal is to soften the water for the discus, injecting CO2 will not do this. It's great for your plants so I'd keep it running. Your pH will drop because CO2 is an acid but the TDS of your water will not change.

Unless your discus are showing stress I wouldn't bother messing with the water chemistry. Fluctuating CO2 won't harm the fish as long as it's not crazy numbers. It will likely encourage algae though.
 
Went Crazy - The CO2 tank dumped lots of CO2 into the tank at once. I set it for about 1 bubble per second, but a some point during the day (I am not home), it started realeasing a lot more. The discus were on their sides and some were at the top trying to get air. I figured with the pH monitor, this would prevent it from occuring again...ie large amount of CO2 would cause large pH change, causing system to shut off.

As for the 8 pH, my discus do not have a problem with it. They are doing fine. They really only need a low pH for egg development.

Using the pH reducers was a mistake on my part. I am going to gradually change the water until it gets back to 8.
 
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