GH/KH

[lochness]

A little history on my 90gal 4ft. tank to be sure I don't omit anything that might be useful.

2 winters ago I was out of town during a snowstorm and a blackout – due to the weather I couldn't get back home in enough time and my entire tank went bellyup. Needless to say I went into a mourning stage and just siphoned the gravel and cleaned it up of dead plants and fish but I left the filters untouched and didn't add fertilizer. Each time I did a water change or topped it off, I used Prime water conditioner. I threw out the submersible heater that short-circuited during the storm.

I left everything running as if I had fish in it minus a heater and what little plant daughter shoots survived I left alone (I had used Flourish tabs in the gravel in the past) Fastforward 6mos later and I decided to do another gravel siphon when to my surprise a lone female cherry barb emerged that I had not noticed AT ALL – it might have been a juvi at the time that I thought all the fish died.

So since then, all that had been in the 90 gal is this sole survivor cherry barb. As recently as 2 weeks ago, I decided to get serious about it again and give it another try. I added a new submersible heater and did 25% water change.

I wasn't sure if I should consider my tank *old and established* or if it would kick in as a new tank once I added some more inhabitants. I did some water changes and squeezed out the sponges sitting in the 2 Filstar XP3 (L) canister filters in a bucket of aquarium water. I left the ceramic cylinders media alone & I added new zeolite pouches. I did the following water tests:

Temp: 78 F

Ammonia: 0

PH: 7.2 (my tap water is 7.4)

Nitrites: 0

Nitrates: 0

My cherry barb, which had been looking understandably pale, looked so much better – fuller from feedings and coloring as she should have. My small daughter shoots looked better as well. Admittedly I had never done a GH/KH testing in my life of fishkeeping and I had been very successful (even breeding cherry barbs and sewellia lineolatas), up until the snowstorm.

Feeling confident that things were in order, I went and purchased 6 Glofish tetras. After a few days I did another test and everything was great except the ph which went down to 6.0 – I figured the 7 inch real bogwood in the tank was somehow making it drop (it stopped leaching over 5 yrs ago but I wasn't sure it if wasn't affecting the ph or not). Ignoring everything I learned, I purchased 3 black phantom tetras I saw in LFS.

So I now have 10 fish and all parameters except ph are perfect after 2 weeks. PH keeps dropping and went as low as 6.0 – I realize fish can adjust to PH changes but this was still alarming and odd. It could be I didn't siphon out all of the Flourish tablet remains and it was dropping my PH or maybe that 7 inch bogwood is the cause or it was a combination of the 2.

I decided it was time to research. I bought a GH/KH testing kit yesterday along with 5 lb bag of crushed coral. I added a handful in a mesh bag of the crushed coral into one of the canister filters last night and just did a water test. PH is now at 6.4 which is better but still doesn't answer my question as to why it was dropping so quickly. But it does show that the crushed coral is keeping it from dropping any further.

Now on to the real reason why I am posting. I am clueless about GH/KH. Am I correct in guessing that my tank is both hard and acid? Here is what I discerned and please correct me if I am wrong.



GH – 12 drops to turn green = 418.8ppm

KH – 4 drops to turn bright yellow = 71.6ppm

total is 490.4ppm ?



Also, how do I know when it is time to change the crushed coral or will it just dissolve mostly from the acid eating it away?

Do I purchase a water softening pillow? What should I be aiming for in terms of GH/KH and how do I go about it?

I'd like to add a catfish eventually as that is where my heart is at, but not until I get things stable and find a suitable species.


Thank you for taking the time to read this and imparting your expertise.

(orig posted @ seriouslyfish)

[lochness]

After a full day of researching I finally found an article that explains it in layman terms and I finally understand it better - sharing the link here for anyone else that might find it useful
http://www.tropicalfishkeeping.com/memb ... ium-73276/

[PseudaSmart]

Since you have a well written post, done your own research, and provided information I felt it was important to give you a similar but shorter response.

First I want to commend you on starting over as losing a tank is hard.

It is obvious that you want to do everything correctly but please slow down. Your issue is not that serious. For the ph to take two weeks to drop down to 6 is actually rather slow and going below 6 is not like falling over a cliff. The easiest solution would be to do 25% WC daily until the ph of your tank reaches around 7. Most freshwater fish can thrive in dechlorinated tap water.

Other observations, I think you converted the GH wrong. 12 drops usually is 214.8 ppm. Did you at least rinse your bio media? Could be buildup.

So here is tried and true advice
Do not chase numbers. Staying at a perfect 7 does not score bonus points
Always adjusting ph, GH, KH causes more stress then a stable high or low number.
What is the GH/KH of your tap water. Chances are it will be in a normal range.
You said the barbs spawned before so they liked your tap water. Why mess with it?
Your tank while technically cycled can only handle a light load at first.
Do not add a lot of fish at first. I think you added about the max for the first month.
Softener pillows. Unless your water is liquid rock they usually are not needed.
Crushed coral in freshwater is used mainly for African cichlids. Not for SA and Asian fish.
My suggestion is to remove it once ph is stable.
Old bog wood has stabilized if the water is clear. Not a problem.
Over feeding is the number one issue to water quality followed closely by not performing water changes.

Aquariums have been a part of my life since the 1960s. I road the waves of progress and technology and tried the time saving chemicals and gadgets. The simplest solution is to do regular WC's, clean the gravel, and clean the filter.

Relax and enjoy,
Jim

[Bas Pels]

Having studied Chemistry, I knew I would understand the waterchemistry, but how can a general hardness could be higher than a carbonate hardness

But then I realized, dissolving NaHCO3 (sodium bicarbonate) in water in water does increase the KH but not the GH. GH is just not general.

GH measures only Ca++ and Mg++ ions in the water.
KH only measures the CO3-- and HCO3- ions in the water.

And, as stated, NaHCO3, Na2CO3 are therefore not 'seen' by measuring GH. And adding MgCl2 will increase the GH without doing anything to the KH.

Still, for the fishes it will not matter much whether NaCl or CaHCo3 is dissolved.

Fishes from hard water take their calcium (Ca) from the water in their gills, so they will nead calcium in the water, but for the rest? All ions er felt the same way.

Using droplets of reagens to measure the GH is therefore not the best way to know your water. It is mch better to measure the condutivity, which measures all ions.

Blackwater, hower, has many not-ions dissolved, and therefore a natural water with a conutivity of 5 microsiemens per cm could for a fish correspond very well to tankwater of 50. But that is another matter.

[lochness]

Since you have a well written post, done your own research, and provided information I felt it was important to give you a similar but shorter response.

First I want to commend you on starting over as losing a tank is hard.

It is obvious that you want to do everything correctly but please slow down. Your issue is not that serious. For the ph to take two weeks to drop down to 6 is actually rather slow and going below 6 is not like falling over a cliff. The easiest solution would be to do 25% WC daily until the ph of your tank reaches around 7. Most freshwater fish can thrive in dechlorinated tap water.

Other observations, I think you converted the GH wrong. 12 drops usually is 214.8 ppm. Did you at least rinse your bio media? Could be buildup.

So here is tried and true advice
Do not chase numbers. Staying at a perfect 7 does not score bonus points
Always adjusting ph, GH, KH causes more stress then a stable high or low number.
What is the GH/KH of your tap water. Chances are it will be in a normal range.
You said the barbs spawned before so they liked your tap water. Why mess with it?
Your tank while technically cycled can only handle a light load at first.
Do not add a lot of fish at first. I think you added about the max for the first month.
Softener pillows. Unless your water is liquid rock they usually are not needed.
Crushed coral in freshwater is used mainly for African cichlids. Not for SA and Asian fish.
My suggestion is to remove it once ph is stable.
Old bog wood has stabilized if the water is clear. Not a problem.
Over feeding is the number one issue to water quality followed closely by not performing water changes.

Aquariums have been a part of my life since the 1960s. I road the waves of progress and technology and tried the time saving chemicals and gadgets. The simplest solution is to do regular WC's, clean the gravel, and clean the filter.

Relax and enjoy,
Jim

Thnx so much for your post and your encouragement

You are correct that I did the wrong conversion on the gh

I did a 25% water change this morning and my tests were: gh - 11 and kh - 4
the ph is at 7.0 all other parameters remained at 0 (I removed the crushed coral this morning as well)

(forgot to add ph of tap water is 7.4 the gh is 10 and the kh is 4)

I will slow down lol - I am just excited at having the tank up and running again.



@ Bas Pels - ty for your informative post - in my research I read just that and tho it goes over my head, I favor more info over less