My dhk is running at 17 right now and i am feeling like that is a bit high......My calcium is at 460 ppm, ph 8.2. I am using API test kits. I know i most likely need to get the dkh down but how do you do that, everything i have seen is people trying to raise theirs. I have not been dosing with anything as of yet.

Yes, 17 is high.

What are you adding to your tank?(please list everything you are adding to your tank) Are you adding purple up or kalk or any two part type additives?

Lets find out why your alk is so high before we try to lower it.

i added a few drops of purple tech last week, but have not added anything else. that is the only thing i have added to it since i havent decided how i am going to dose it yet. i have also done a water change since adding the purple tech.

what is purple tech? is it the same as purple up?
how old is the test kit?; api has a number on top of their bottles: mine is lot 59A0908, the last four numbers represent month/ year. if yours is old, maybe you need a new one. a year is about as long as it should be relied upon, acc to what ive read.
have you tested the new water you made the change with?

purple tech is basically the same as purple up. i will have to check the date on the kit when i get home. i just bought it but the store might have been selling an old kit :/ i am using ro water from dpa i am getting some more today so i will check that too if my kit is in date.

What salt are you using and what salinity/specific gravity is your tank water.


if your not adding anything, no Alk supplements, no PH buffers, purple up or anything like that. And your using good RO water and the SG is correct then i would agree that its either a bad/out of date test kit or a bad test kit user Have you redone the test again and gotten the same results?

i am using instant ocean and my sg is 1.025. i have done the test 3 times now and gotten the same results. the directions say to add one drop at a time and shake in between until the color changes so thats what i have been doing. i am thinking its probably a bad/old kit, but i will check the date later today.

Has the dkh always been that high? Or did it all of the sudden get high?

When you first set up your tank did you use RO water?

BTW, that was a joke about the bad test kit user

lol i wasnt offended, and that could be a possibilty. i have used ro water from the start, all the corals are looking happy. i just got the kit last week and it tested high then so tested again after my weekly water change and it is still high.

If everything is looking good then i wouldnt worry too much, and i wouldnt do anything just yet untill we figure out whats going on.

If the dkh reading is correct, it is a bit high but shouldnt cause any problems. Sometimes people that have sps tanks have issues with high dkh (burnt tips, tissue necrosis) but that doesnt always happen and i dont think ive ever seen something like that happen with lps or softies, and fish dont seem to care.

Do you have any of the RO water sitting around without salt in it? You might want to test that. If DPA has really alkaline water and a faulty RO membrane that could be the cause.

One more question, when you are doing the test, do you stop adding drops as soon as you see the color change or are you still adding drops untill you get a full color change?

One more question, when you are doing the test, do you stop adding drops as soon as you see the color change or are you still adding drops untill you get a full color change?
+ 1 on that question!
are you using the stopper to shake the solution or are you giving it the finger?
exactly 5 ml also?
and best to put drops in with the bottle completely vertical, so drops are same size each time.
and just in case:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12.

i am only getting it to change from blue to greenish yellow not a full yellow no matter how many drops i put in. So its 17 drops for any color change at all. I do put the stopper on every time and i use a syringe to get 5 ml instead of the line on the tube. The date on the bottle is 10/08 does that mean it is good for a year after that? I am getting ready to test the water i just picked up from dpa, but i had him test it with his kit before i left and it only took 1 drop to turn yellow with his kit.

ok i just tested the plain ro water, no salt and 1 drop didnt even chnage the water and 2 drops made it the faintest yellow. I might go back to dpa and take a water sample and have him test it to be sure, but it seems as though the kit is fine. Thats a little more concerning i think since i was hoping it was just a bad kit. Since the water is fine and the kit seems to be fine the only thing that leaves i guess is if i got a bad bag of salt or purple tech makes the water go crazy I am starting to get another diatom bloom though after the first one cleared up, if that is helpful information.

ponies999 wrote:ok i just tested the plain ro water, no salt and 1 drop didnt even chnage the water and 2 drops made it the faintest yellow. I might go back to dpa and take a water sample and have him test it to be sure

THIS IS A GOOD IDEA,

but it seems as though the kit is fine. Thats a little more concerning i think since i was hoping it was just a bad kit. Since the water is fine and the kit seems to be fine the only thing that leaves i guess is if i got a bad bag of salt or purple tech makes the water go crazy

WHAT'S THE DOSAGE FOR P.T? DID YOU DO IT EXACTLY, SINCE YOU ORIG'LLY SAID SOME DROPS WERE PUT IN . REALLY DON'T THINK THAT STUFF IS NECESSARY ANYWAY.

I am starting to get another diatom bloom though after the first one cleared up, if that is helpful information.

YOU ALSO SAY

i just picked up from dpa, but i had him test it with his kit before i left and it only took 1 drop to turn yellow with his kit.

if he turns it yellow w/1 drop and you need 2 to turn it the faintest yellow, seems like it's at least 100% difference in the kits that would put your water correct. my thought is to get dpa to test your water

You certainly could have a bad test kit. Sounds like you are using it right. If you do go to DPA bring your kit also and both of you test a sample from the same tank. He might replace it for you if you got it from him. If you get a new kit i would test it while your there because it could be the whole batch of kits and not just your one kit.

Diatoms come and go, i doubt it has anything to do with the dkh (even if it is high, which were really not sure if it is high)