KH and GH Are Extremely Low - Aqua Soil?

[LindaC]

I am very pleased with the way my plants are responding to the new Aqua Soil, it's amazing, however, as of this morning, the KH is below 10, GH is below 20 and the PH is at 6.0. I haven't even started injecting CO2 into this tank either.

The tank is currently cycling and most of my fish are in my larger tank. I have 3 Danios in this tank to help it cycle faster. I want to move my apistos or kribs over to the 10 gallon, once the bio-filter is established but now I'm a little concerned about the parameters. Anything I can do to rectify this problem?

Also, would adding CO2 be a problem with KH so low, won't it bring the PH and KH even lower?

Many thanks!
Linda

 

[7Enigma]

Are you talking ppm or degrees? I'll assume ppm since 10degrees KH is pretty darn high! What is the pH of your tap water? Do you have any driftwood that would be lowering the pH? A pH level that low will definately slow if not stop your bacteria from multiplying. And adding CO2 would not be a good move as it would definately lower the pH, probably drastically.

If you are indeed at 10ppm KH I would very slowly (since you have fish in the tank) raise your KH by using baking soda. This is a 10 gallon correct? I'd take 1/16th teaspoon and mix it with a cup of tank water and add to the tank. Maybe 1/2 the cup, and then wait an hour and add the rest. Measure your KH and pH levels again. Aim for 1-2 degrees (15-30ppm) max increase per day. I prefer 0.5-1degree increase per day, just to ease the fish into harder water conditions easier. Just remember:

If you do decide to buffer the water with baking soda you need to match the tank level at each water change!

 

[LindaC]

Other than adding a little baking soda, is there anything else I can do? My tap water PH, when left to sit overnight was a lot higher, to be honest I forget now, It's been a while, something like 7.6. When I called the lab to inquire about the water out of the tap, the scientist I spoke with said the PH of water in my city is high, between 8.9 - 9.4, KH is 40 and GH is 14.5 parts per million. I have very soft water.

I do have a very small piece of drift wood in the tank, would that make it that much lower? I truely believe it's the Aqua Soil, it wasn't nearly that low to begin with. Please let me know if there is anything else I can do. Should I just forget about adding CO2 to this tank? I guess putting Aqua Soil in my 29 gallon tank with pressurized CO2 is out of the question then.

 

[JRagg]

Crushed coral also works for raising KH. It's sort of a "slow releasing" type thing and will start to creep up over a few weeks. You can either put it in a media bag and then into a filter, or spread some of it over your substrate (though I doubt you want to do the latter since you spent all that money on aquasoil). Any place that sells saltwater stuff should sell CC. It's generally very cheap if you get it at a LFS. I've even seen it at places like petsmart, though it was more costly than at a LFS.

 

[LindaC]

If I add baking soda or crused coral and raise my KH, will I then be able to safely add my fish back to the tank and will I be able to inject CO2? The crused coral and baking soda is not going to raise my PH, so I'm quite concerned about that. Any thoughts?

 

[rich311k]

The CC or baking sode will raise your KH and therefore your PH. If you add enough to get to 3-4 kh or so, your tank will be stable when you start you CO2 injection and your fish should be just fine.

Right now your KH in tap is 2.2, which is why the substrate is effecting your PH so much you have very little buffering. The baking sode or CC will add a buffer and stabilize your tank. I have never used the Aquasoil and wonder if the effect on KH is short term or long term.

 

[7Enigma]

I'm not a fan of CC for several reasons:

1. You have no idea exactly how high or quickly your KH will raise.

2. At water changes your water will bounce around KH values unless you are doing small PWC's.

3. Can't remember right now, but I did have a 3rd...

Anyways, it is odd that your pH is so high from the tap with such low KH and GH levels. I'd be interested to know what is causes all of that alkaline to be present.

I would recommend since this is a planted tank that you wish to add CO2 to use baking soda. It is very easy to use, you know exactly how much you will add at each water change, and there will be no pH fluctuation due to KH during a water change. (The pH will obviously go up during a water change once you are using CO2 since the tap water you are adding in will not have that high CO2 level.)

 

[czcz]

It is the AquaSoil that's lowering it, and while buffering KH back up is a fine idea, it kind of defeats your fancy substrate. Many people running AquaSoil are doing so in 0-2dKH with CO2 injection and fish stocks. It runs counter to many traditional and effective methods, but consider moving forward with the current parameters. I believe in nature Apistos see way way acidic pH in the blackwater rivers.

7Enigma, maybe 3. was Steve Hampton's posts that CC dissolves faster as acid (CO2) increases, so CC is even more unstable (your 1st point) with CO2 injection?

 

[LindaC]

Well if I can add CO2 to this tank and my fish won't be affected by my leaving the KH alone, then I won't bother raising it. I thought for some reason that it might have a bad effect on the fish. I mean the PH will be pretty low.

I'm very familiar with adding baking soda to my tank, as I already do so in my 29 gallon. I've been adding 1/2 tsp with every water change, ever since I started pressurized CO2, with my KH being so low anyway, I was told it would be a good idea. I'd rather not do this if I don't have to.

There's only one more thing that concerns me though and that's my bacteria not multiplying with a PH so low, is this true? I do not intend to add my apistos or kribs to this tank for at least 3 more weeks, if it's cycled by then. I read on APC that it's a good idea not to add fish to a tank set up with AS for atleast 4-6 weeks, is this because of the cycle factor or is there another reason? Anyone?

Many thanks for your responses, you've been very helpful, as usual! This is such a great site!

Linda

 

[czcz]

Its true that having some KH is wise for CO2, and its true that keeping pH from getting to acidic is good; however, with AquaSoil (and softwater) tanks' recent popularity, many are finding that it's not the big deal we feared. There's still a lot with CO2 injection, KH, and pH we're learning. Tread cautiously, but there's a large group of people doing what you plan with little-no issues.

No help with bacteria at low pH and stuff. FWIW, when I converted one of my tanks to AquaSoil I did so with a high fish stock compared to volume for months (Blue tetras, Kuhliis, Hillstream loach, Otos, Cherry barb, snails and shrimp) and don't recal any fish die in that tank during that period. I did acclimate slowly when reintroducing the fish, though.

After a couple months, AquaSoil's effects lowering KH starts to die off, by the way. With regular water changes it will gradually come back to tap water levels unless you mix with RO/DI or something.

HTH

 

[LindaC]

Thanks czcz, you've been very helpful! I'll just continue on and hope it cycles on course, as I was planning on putting the kribs in that tank, hopefully, within the next 3-4 weeks, which will give the tank a month with the new soil.

 

[7Enigma]

There's only one more thing that concerns me though and that's my bacteria not multiplying with a PH so low, is this true? I do not intend to add my apistos or kribs to this tank for at least 3 more weeks, if it's cycled by then. I read on APC that it's a good idea not to add fish to a tank set up with AS for atleast 4-6 weeks, is this because of the cycle factor or is there another reason? Anyone?

Linda

It is true that the bacteria will severely slow if not stop metabolism if your pH gets into the 5's. The nitrIte to nitrAte bacteria (also unfortunately) suffer from low pH worse than the ammonia to nitrIte bacteria.

So best case scenario your plants use all of the available ammonia (I would definately plant heavily from the start to avoid algae issues if there is leftover ammonia) and you have a wonderful tank.

Worst case scenario is that whatever pH your tank ends up at after introducing CO2, is high enough to have nitrIte being created, but too low so that no nitrAte is produced. This could be dangerous as your tank would essentially be stuck with rising nitrIte levels that neither your biological filter, nor plants could use.

I always feel that in any planted tank WITH fish, the fish come first. If you find your levels going above detectable, I would increase the KH to help the pH stay at more neutral levels.

 

[LindaC]

Makes a lot of sense, oh I'm so confused. It certainly wouldn't hurt to add a little baking soda, the soil is still going to be great for the plants whether I add it or not and your right, the fish are a lot more important then the plants. If I wasn't going to add CO2, I wouldn't be so concerned. My lights are too high to go without it (2 19 watt screw in compact flourescents). Although I've been adding Seachem Excel and the tanks been looking great, so far.

I really don't want the PH to go any lower than 6.0, right now, according my Hagen test kits, it's around 6.2, it's hard to tell with the color range. I've been adding 1/2 tsp to my 29 gallon tank with every water change and it keeps the KH in that tank at 70, it never goes lower or higher, so it's very easy to do.

Thanks for all your help!
Linda

 

[Zezmo]

FWIW, my main tank which runs the Aquasoil typically has a Kh or less than 1. My Ph often runs right down at 6, if it is lower I can't test that. Unless you are keeping African cichlids in there, who I think need really hard water. Most common ornamental fish will do fine. A lot of south Americans may in fact thrive in that water. coughdiscuscough
As Cz indicated, the Low Kh is a desired and expected affect of using Aquasoil.

 

[sherry]

my kh is less than 1. my gh is buffered up.. my fish are fine. i have aquasoil and soft water to begin with and i inject co2. the plants and the fish do great. I started turning off co2 at night to give fish a break. I no longer worry about consistent ph, just consistent kh.

oh and tonina belum which when belly up on me when i only buffred 1/4 t of baking soda, is growing great with no buffering. I can't convince my rummies to die, try as I might to tell them to "go to the light" so I can replace with pencils, and my apistos have never been happier. a bristlenose pleco doing great as well

 

[LindaC]

*LOL* Thanks Sherry, you're too funny with your rummies, isn't that always the way, you want them to go to the light and they stay as hardy as ever. So you are not buffering your water with 1/4 tsp of baking soda, or you are?

Thank you for posting, this is a big help to me!