KH help???!! advice? knowledge!!

what would be happening in my tank if the dKh was 7-7.5 drops for 2 days, lights on or lights off? would i see any changes in the critters i have? i just did my regular weekly maintenance of changing 7 gals 1.025+ which matches my tank h2o and that pure water tested around 12 drops, which i think is a bit high. no other params are off. 8.3-4ph 0’s the rest of the way, temp 78-79+, no fish or invert trouble. everything looks good and eats. my thinking is the test kit is a bit old. last 4 digits of api number on the bottle is 0908, which i read long ago represents expiration date. i hope my thinking is right.

What does 7-7.5 drops represent?

1 drop turns saltwater blue, ian. instructions say count each drop until water turns yellow. each drop represents a degree of kh hardness, i think. there is a conversion rate for freshwater [1 drop x 17.9 = ppm i think] for salt, i don’t know

i wikipediad and found that the drops are degrees of german hardness
The ‘K’ in KH comes from the German word ‘karbonate’. KH is a measure of bicarbonate and carbonate ions that act as buffers in the water to prevent the pH dropping or changing sharply therefore my 7. One degree KH is equal to 17.9 mg/I (ppm) CaCO3. It’s also measured in degrees. The degree symbol may be replaced with a d (ie. 2 dKH).
my 7+ reading X 17.9=134, that scares me and i’d think if that were accurate things would be dying right now.

Assuming that is correct 7.5 * 17.9 =134.25ppm = a dKH of about 7.5, sounds good to me (looks like just count the drops and you get the dKH #, cool its easy).

I think that # is in the range, maybe a little on the low side. This just means your buffering ability is slightly reduced and there isn’t as much carbonate available for your corals/coraline.

You can raise it by adding some buffer in.

EDITED: For legibility, line feeds make all the difference.

For reference, in ppm my tank is up around 240.

thanks ian, and i have hardness envy. butdo you think i would see any critter reaction? it seems more than a bit on the low side to me, esp’lly looking at your number.
will add some kent probuffer kh tomorrow, since i added some this am. made no difference in the kh.

Go slow, I don’t think you are overly low and I am more on the high side, I believe a good target is around 8-12 dKH.

always slow, like an anemone

[quote=“moliken, post:7, topic:1301”]
thanks ian, and i have hardness envy.[/quote]

Oh, nevermind.


I feel so much better knowing that im not the only with a 3rd grade sense of humor!!

“I feel so much better knowing that im not the only with a 3rd grade sense of humor!!”

i always thought that mine was a middle school mentality.

but everyone agrees that the 7.5 dKh should not be a worry for me??

I think 7DKH is the bottom end of the scale for safety. should something happen or you neglect chemistry a few days a low DKH will drop the PH and hamper the corals. i run at low dkh. i shoot for 8-9 but often falls to 7. but then i bump it up. and keep calcium up with additions and kalwasser to improve PH. seems to work.

thanks, well put kapten. i was worried about the low end also. added kent probuffer this am; now at about 8 1/2 drops. adding again 20 ml for my 65 gal tank tomorrow am.

While I agree with Ken that 7 is low I would also go slower raising it up since it effects pH, calcium and Mag. Large changes either way are stressful.

no rapid changes, not large ones either. tank + sump is probably 70 gals total, and i’m putting in dosage for 50 gallons. 8.5 drops just now.

I have found 1 or 2 DKH bumps cause no problems for my tanks at all. It’s all within tolerance ranges. 3 or 4 bumps per day~,~ give some pause to consider. No rush. take yer time.

yep. kent’s sez no more than 1/2 ml per gal per 12 hours. that for me is 70gal X .5 for 35 ml. i put in 20 ml per day in the morning, so i think i’m safe. there’s very little upwards movement and i just do not want a fall.