Experience with SeaChem Acid Buffer & Alkaline Buffer

[_Nemo_]

Does anyone have experience with SeaChem Acid Buffer and Alkaline Buffer?

I know this goes against the established wisdom in this hobby, but I maintain my swimming pool water chemistry using chemical additives (ph, kH, gH, and sanitizer). Why is it difficult to achieve a stable chemistry in a FW tank with additives?

So, I went ahead and purchased a 300g bottle of Seachem Acid Buffer (came up to $16 with taxes). I then filled up a 22L bucket with tap water (kH=2, gH=3, pH=8.0), added the conditioner and a tiny amount (1.0 gram) of Acid Buffer. I could measure this exact amount using a laboratory grade electronic scale I have. With this, the pH dropped to less than 6.0 and the kH to about 1 dkH.

I threw in a heater and let the water sit in the bucket till the next morning then measured the pH and kH. The pH was at 7.4 and hK at about 1.0-1.5 dkH.

In the evening that day, I started over again with fresh tab water (warm water this time). I then threw in (same old 22L bucket) a 50W heater and maxijet 1200. I figured this should speed up equilibrium by vigorous mixing and aeration that gets rid of the CO2 produced by the addition of Seachem Acid Buffer. Subsequently, I added baking soda very gradually until the kH reached 6 dkH. I figured this is high enough buffer to stabilize the pH, right? Only then did I add the Acid Buffer – a lot more this time – to bring the pH to 6.0.

I let the bucket mix for 10 minutes, then measured the parameters again: kH = 5.5 dkH, pH = 7.0! I thought to myself, ok, this is a dynamic reaction and will require time to stabilize. So I added more Acid Buffer to bring the pH back down to 6.0, and let the power head and heater running overnight.

When I tested the water in the morning the pH was > 7.6 and the kH = 3.5!

That same evening, I started over again. This time I did not use baking soda, but an AlkalinityUp product I used for my swimming pool. Luckily with this stuff, I could calculate the exact dose needed to set the kH to the desired level – no trial and error necessary. I set the kH to 4.5, and added enough Acid Buffer using a
1:1.3 ration as recommended on the bottle to produce a pH in the range of 6.5 as per charts on the bottle.

Next morning, the pH was > 7.6, kH was 3 dkH! What did I miss?! I figured that when adjusting the pool waters, we usually have to adjust all three parameters, pH, kH and gH. So I dug up the old bucket of CaCO3 Up and read the label. As it turns out, we aim for and gH of 200-300 ppm (11-16 dH) in the pool. This is too high for my purposes since I would like to keep soft water species. I figured, I should try a 6 dH instead.

I dosed for 6 dkH, 6dH, and a pH of 6.0. Within 15 minutes, the pH was back up to 7.2!

Arghhhhhhhhhhh!!!!!!!!

Reading the label on Seachem’s Acid Buffer bottle, it says that the product lowers the pH and produces CO2. Hmmmm, is this * HOW * it reduces the pH? Is aeration driving the CO2 out thus causing the pH increase?

I don’t know. But the label says that the product should be used in conjunction with Alkalinity Buffer to produce the desired (stable) pH. But it mumbles something about adding it directly to the tank for best results … I DON’T THINK SO !! At least not until I get stable water parameters in a bucket for a couple of days.

At this stage, I am very skeptical about Seachem claims regarding the combined use of Acid Buffer / Alkalinity Buffer. The best way to verify, obviously, would be spend another $20 and try it. But again, the company’s literature mumbles about having to “trial and error� the correct combined dose. Well, that does not make me comfortable.

So .. does anyone have any success / experience with SeaChem Acid Buffer / Alkaline Buffer or other similar products? Why is it that pool water can be balanced but not aquarium water?

[medge00]

i dont think buffers always work that well. how big is your tank? have you considered using RO water to bring down the pH? or, if you can harden your water a little, try CO2. what is your ph and hardness straight from the tap and what are they after you let them sit overnight?

Why are you fighting the water? Have you tested the pH of your tap water after it has rested for at least 12 hours and then again at 24 hours? With a kH of 2° your natural tap water pH should be around 7.5 If it were my water I would bump the kH up a degree or two and use CO2 injection to lower the pH.

What you are seeing is normal. It's very hard to keep water acid if there is buffering present. I'm betting that you keep your swimming pool alkaline and not acid. In fact with any amount of kH present in the water you will have an almost impossible time using pH adjusting chemicals to maintain a acidic pH. But CO2 will do the job just fine.

If you were trying to balance your aquarium to an alkaline environment you would have no problems. I do it all the time for my shell dwelling cichlids. But keeping the water acidic with kH present requires the use of CO2. It's possible to do it with other additives but you pretty much need a continuous supply.

Check my FAQ for a link to a great water chemistry site. I get the feeling you don't quite understand the term buffering.

[_Nemo_]

This is great information Rex. Thanks for the feedback.
You are right, my memory was quite rusty wrt the interaction between pH and kH - It's been a long time. I had to polish up a bit, but I think I'm set straight now.