Low kH - keep adding buffers?

[threnjen]

I have city tap water with extreme softness (1/3-1/2 grains per million) and no kH. To buffer this, I have a large amount of crushed coral and a cuttlebone in my sump.

My tank pH is already far higher than the water coming from my tap (7.5 in tank, 7.0 from tap).

Unfortunately although I have raised gH to 5, my kH remains low, stuck somewhere in the 2 range or even lower (between 1 and 2)

I'm really hesitant to keep adding buffers and raising my pH even higher. Already at this point I wonder if the pH discrepancy from tap to tank warrants two 30% WC per week instead of one 50% (oh joy...)

Should I just add more coral?? It seems curious that all of my additives seem to produce so little results in the kH department. I have at least 4 cups coral in the 110g, plus the cuttlebone.

 

[Delapool]

Did you come up with anything? Just going through this as well although not so much a battle. Added cuttlebone and shells a few days ago and so far not much impact but I've only added about 1/2 a cup to start and tank ph is 7.3 to start with.

I have been using seachem reef carbonate which will raise kh but I swear it knocks the stuffing out of the plants. Also I have used a ph buffer powder in the past which is plant safe, but wanted to try the cuttlebone.


GH of 5 doesn't seem too bad and still in the soft range looking at the table below?

Water Hardness and pH in the Freshwater Aquarium

 

[threnjen]

No, nothing different. Just figured no one had any ideas (and bumping post not allowed)

Yeah the gH is fine now and the pH is too high and yet I still can't seem to get any buffer of kH! I just don't think I can add any more stuff! Like I said I'm already worried about pH discrepancy with water changes with such a swing from the tank to my tap.

It keeps getting drilled in to me that kH of absolute minimum 3 is needed in a planted aquarium.

I really don't want to have to go to chemicals Everyone was sure that some coral would help. Urrrggghh

 

[Delapool]

No, nothing different. Just figured no one had any ideas (and bumping post not allowed)

Yeah the gH is fine now and the pH is too high and yet I still can't seem to get any buffer of kH! I just don't think I can add any more stuff! Like I said I'm already worried about pH discrepancy with water changes with such a swing from the tank to my tap.

It keeps getting drilled in to me that kH of absolute minimum 3 is needed in a planted aquarium.

I really don't want to have to go to chemicals Everyone was sure that some coral would help. Urrrggghh

Hope it comes good. I've only got the strips for gh and have just written 'fine' for every reading - problem solved!

I'm trying the cuttle bone has in theory that should react more quickly.

 

[Old Scales]

What does the Seachem (equilibrium, I think) have in it as far as GH & KH? since your water is darn near as soft as distilled, I wonder if it would work? That way you avoid separate chemicals. ??? OS.

 

[Delapool]

I also wondered if there was a seachem product that might help. I saw in another forum that this had been used (link below). On almost the last line it talks about mixing products but I always thought kh and ph were linked. I'd never heard of phosphate buffers so learnt something new.

Seachem. Neutral Regulator FAQ

 

[threnjen]

What does the Seachem (equilibrium, I think) have in it as far as GH & KH? since your water is darn near as soft as distilled, I wonder if it would work? That way you avoid separate chemicals. ??? OS.

I must be totally brain dead, I HAVE Seachem Equilibrium and used it for a few water changes and then I totally forgot about it. Yes, it should probably really help! Thanks, I can't believe I just forgot about it...

 

[threnjen]

I also wondered if there was a seachem product that might help. I saw in another forum that this had been used (link below). On almost the last line it talks about mixing products but I always thought kh and ph were linked. I'd never heard of phosphate buffers so learnt something new.

Seachem. Neutral Regulator FAQ

Huh... Learned something too. I thought kH and gH could never go up without pH going up.
I really don't want to chemically mess with the pH though.
I wonder if Equilibrium is going to raise my pH too. Guess I better look into it, and remember to actually use it if needed.

 

[Old Scales]

Threnjen,
I have very soft water also with a KH of two. My GH is usually only 3 or 4° also. I have a 29 gallon with pressurized CO2. With this soft of water the pH would go from 6.8 at start to 6.4 by the end of the CO2 dosing. This concerned me because as you know biological activity slows at that point. At every water change I dissolve 1 teaspoon of baking soda in 4 ounces of water and add to the tag. This raises my initial pH at that time to 7.2 that after 24 hours it settles to 7.0. This raised my KH to 5° which is perfect and enabled my pH to maintain 6.8 at the end of the CO2 dosing period. Is there a reason why you are more concerned with the GH as well as the KH? I have found with my plants and inverts my low GH has never been an issue. Also most all community fish adapt and live well at a 7.5 pH. I have researched that general hardness (gh) does not affect pH very much like carbonate hardness does (kh).
As far as trying out the Equilibrium, you could put a gallon of water in a container, test the pH, dose the Equilibrium accordingly, wait one hour then retest pH. That would be interesting. I would be interested in anything you learn about this phosphate-based buffer. It may be a better option for me also as opposed to sodium bicarbonate.
Take care, OS.

 

[ScotJudd]

My tap is Kh 1-2 Gh 4. I upped the Kh to 5-6 using a dilute solution of Bicarbonate of Soda in tap water on water changes. The tap ph of 7.2 rose to 7.4 and falls to 7.2 end the end of the daily Co2 dosing. My plants are growing and sending out runners like crazy. It was trial and error at first, tested out in a 10l bucket. I found that dissolving 2x10ml spoons of bicarb in 500ml of water as my solution and adding 25ml of the solution to every 10l of tap water did the trick. The Ph is higher than I would like but my tetras/Cory's and shrimp seem to be thriving.

 

[threnjen]

Sounds like i may need to go the baking soda route, but i'll try the Equilibrium first.
to answer OS's question regarding gH - i don't particularly care about the gH at all. I am just trying to increase my kH to 3 and the gH rises as a consequence.

I'll gladly run some tests to share with the Equilibrium! Tomorrow maybe when i have some time, not at home today.