hey again got a test kit for GH and KH

[utahfish]

i bought a test kit today so i could figure a little out about my tank. i didnt want to get a bigger kit too much money so the lady at the store suggested GH(general hardness) and KH carbonate hardness.

my GH was 80mg/L and my KH was 80 as well. on the back of the book it said my water was slightly hard and my carbonate is associated with a low
Ph

is there anything alse i can learn from these tests, specifically what my ph is and what my co2 or pottassium level are, without buing another set of test kits?

there is a conversion table on the back of the book but i'm no chemist and it doesnt really make alot of sense. a little help would be greatly appreciated.

 

[George Farmer]

GH is a measurement of your total hardness - usually kits test for Magnesium and Calcium salts.

KH is as you say - Carbonate Hardness. This is a more complex issue and is directly related to pH. The higher the KH the higher your pH. KH is also known a Buffering Capacity or Alkilinity - the water's ability to resist pH fluctuations. It is important to have at least 50 mg/l KH when injecting CO2 for this reason.

You cannot determine pH from KH alone. You will need a pH kit. However I would guess your pH would be around 7.5. One can determine this from a pH/KH/CO2 table. Assume your CO2 level is currently around 5 mg/l as you're not injecting CO2 and you can cross refer in the table.

Here's a good table - http/www.floridadriftwood.com/page.asp?id=16

To convert mg/l into the more commonly used unit of Degrees Hardness (dH) then divide mg/l by 17.9.

i.e. 80 mg/l / 17.9 = 4.5 degrees.

There is no way I know of for the hobbyist to test for Potassium. I don't beleive they make a commonly available test kit and your KH/GH kit has no direct relevance on Potassium levels.

 

[utahfish]

so to find potassium level i would just need to know co2 level and PH right?

i think you gave me the formula for that yeaterday. i think i need to go back down and get a c02 test kit.

also you say atleast a 50 kh when injecting co2 , will injecting co2 raise your KH to where it's harmful? i'm assuming you want to keep your kh level between 50-100 and your co2 levels between what?

 

[utahfish]

i'm sorry i need a ph test kit that way i can calculate kh and ph and get my co2 right?

then if i know my co2 ppm then i can calculate potassium as well right?

I always liked chemistry in high school but it's so confusing and high school was a while ago

 

[George Farmer]

As I said, there's NO easy way to test for potassium.

To calculate CO2 you use simply measure pH and KH then use the CO2 table.

Your KH should remain at 80 mg/l all the time - CO2 shouldn't affect it.

Ideal CO2 levels are 20 to 35 mg/l. It is important to keep a fairly constant level to avoid algae problems.

 

[utahfish]

As I said, there's NO easy way to test for potassium.

To calculate CO2 you use simply measure pH and KH then use the CO2 table.

Your KH should remain at 80 mg/l all the time - CO2 shouldn't affect it.

Ideal CO2 levels are 20 to 35 mg/l. It is important to keep a fairly constant level to avoid algae problems.

thanks. what if your ph is too high? what can you do to lower ph and kh levels?

i have mostly tetras in my tank. neons and red eyes glo lite and black neons, they prefer a lower KH and ph around 6-7 but the buffering capacity for KH to help buffer my co2 is about 81-100. by raising my KH to accomadate my co2 to accomadate my plants i also rasie my ph which the fish dont like.

whats the happy medium, can i attain a low PH around 6.5 and still have enough carbonate to benefit my plants?

if not how do people grow plants in tetra tanks?

 

[utahfish]

iv'e also heard that distilled water will lower ph. when using distilled water do i still need to use the water conditioner in it?

 

[qwikimpss]

With distilled water, i would add conditoner, and, depending on the KH of your tank water you may need to add a buffer to the distilled water, unless youre using ONLY distilled water, thwn you WILL have to use a buffer.

 

[utahfish]

With distilled water, i would add conditoner, and, depending on the KH of your tank water you may need to add a buffer to the distilled water, unless youre using ONLY distilled water, thwn you WILL have to use a buffer.

what kind of buffer?

 

[George Farmer]

You seem a little confused.

You say your KH is 80 mg/l. This equates to 4.5 degrees Hardness.

If you inject CO2 to reach a level of 25 to 30 mg/l then your pH will be around 6.8 - ideal for your fish. Trust me on that, many people keep tetras at much higher levels with no problems. I know of aquarists that have bred Black Neons and Glowlights with pH levels of up to 8!!

In summary I wouldn't bother changing your water chemistry, it is fine.

BTW your KH will STAY at 80 mg/l. Injecting CO2 has no effect on it (unless you have massive doses of CO2 or very high phosphate levels - don't worry yourself about these!)

Most plants only need a KH of 2 degrees (35 mg/l) or higher so don't worry about that either.

 

[utahfish]

thanks gf225. you've helped limit my confusion and i feel more equipped to battle algae and help my plants grow.

than you