dKH

[junyong84]

hi guys, how do u guys raise dKH and maintain it?

What brand of additives do u dose?

My dKH is dangerously low, though i tried to dose it every day, still cannot manage to raise it...

very sad...

[weileong]

Can you give detail of the following:

1. Brand of test kit.

2. Your tank dkh reading.

3. brand and type of addictive.

4. The amount of addictive you're adding.

Have you tried measuring your Ca too? Should be dropping as well.

[junyong84]

i m using salifert test kit.

my dKH is near 7. very very low. i almost couldnt believe it, so i test it again.

using seachem liquid kH buffer.

mine is 4 x 2 x 2 with a 3ft sump. dosing about 1.5capful everyday. doesnt seem to work.

tried using KW to top up during evaporation. no use too.

anyway, my calcium level is just nice. abt 460. no issue abt my calcium.

[planetg]

natural sea water's KH is 7

[weileong]

I supposed you're using the Seachem Reef Carbonate?

I've no details of the volume of your tank so we assume about 400L.

The recommended dose is 1capful (5ml) per 80 gallon (302.8 litres) will raise 0.25meg/L (0.7 dkh)

You add 1.5capful so that only raise abt 0.8 dkh.

Have you tested the dkh before dosing and after dosing to ensure that your dosing is correct?

Probably you need to dose more actually.

What you need to find out is after 24hrs (before dosing) did your kH reading drop or can be maintain, from there you work out the actual dose needed.

btw dkh of 7 is not dangerously low, it is close to NSW levels. I run my reef dkh at 7

[AlfaRomeo]

Also, what your Mg levels at? Too low and Kh will refuse to go up and maintain.

[shoelevy]

Also, what your Mg levels at? Too low and Kh will refuse to go up and maintain.

i agree

i had low Mg problems a mth ago then the kh would drop to 6 from 10 in a matter of 6days

btw, i'm using seachem reef builder the powder form to boost and maintain my kh

it works very well and i like the fact that they tell you one teaspoon raises kh of 150L by 1

this is important as you can manage and control the amt of kh you wanna add

i would highly recommend this

i've given up on those liquid forms that don't tell you how much kh u are adding....

[weileong]

Reef builder dosage is 1 teaspoon (5ml) for every 150L and that will raise the kh by 0.7 dkh not 1dkh

[shoelevy]

Reef builder dosage is 1 teaspoon (5ml) for every 150L and that will raise the kh by 0.7 dkh not 1dkh

oh yeah

sorry!

made a mistake

i did my own calculations with the recommended dose, its actually one 3ml(not 5ml) teaspoon will raise 1dkh for 100L

been dosing like that ever since i started with the hobby so its tested and proven and safe

weileong...u also mistake...the instruction is half a level teaspoon (5ml) will raise the kh by 0.7 dkh, not 1 teaspoon

1 teaspoon will raise dkh of 150L by 1.4

[weileong]

I use the 5ml teaspoon

[shoelevy]

haha

ok

whatever our preferences, make sure you use according to instruction if you use it junyong84

[djviper]

sry to hiijack ur thread but i wanna ask reef buffer 8.3 can also increase dkh right?

[shoelevy]

according to the instructions yes

but it raises ph too meaning it doesn't give good control over ONLY ph or ONLY kh

[junyong84]

my mg used to be very low. manage to pump it up.

maybe i shld try the powder form then...

very shock to see my dKH so low...

[prec]

any good way to pump Mg up? im tryin not to get epsom salt method.

[junyong84]

any good way to pump Mg up? im tryin not to get epsom salt method.

juz dose mg additives lor.

i m using aquaz product. very good. anyway, i don't follow the instructions. i pump it daily til the level i wanted

[shoelevy]

any good way to pump Mg up? im tryin not to get epsom salt method.

i use tropic marin bio Mg

so far no regrets

some other lao jiaos here are also using it so i recommend it

[Reefbum]

any good way to pump Mg up? im tryin not to get epsom salt method.

Cheap and safe method is to do water change and raise your SG higher.

[Ekia]

any good way to pump Mg up? im tryin not to get epsom salt method.

epsom salt is ok. been using it for a couple of times. Cheap way to raise Mg espcially if u have a huge tank. You will go broke using those aquarium addictives to raise Mg. Some of the guys here had experienced it

[madmac]

hi, I wonder... if there are reef keeping publications that show that Mg causes dKh to be low. I've been trying to find for such articles. From my 'limited' understanding/reading... it doesn't. Alkalinity drops are more likely due to other factors OR a combination of them rather that solely due to Mg ... the thing is I don't think (I may be wrong here) tt Mg has even a remote connection to dKH as what some of you here say it is.

As most here would know that Alkalinity is dKH(another measure) and in this article : Alkalinity it was pointed that bicarbonate make up 89.6%, while carbonates 6.7%. Thats a total of 96.5%, leaving the rest to a few others... there was an item called magnesium monohydroxylate, whose "Relative Contribution To Alkalinity" is only 0.1% !!

I think I've read somewhere of the direct relation of Mg to calcification of corals, however thats not what this topic is.

junyong84,

You'll best appreciate this hobby if you understand/find out why your dkh drops(as it always will). A dKH of 7 is not as dangerously low as its possible effect on your pH. ie. a low dKh can allow wild swings of your pH which can harm your LS. This article show how to correct your ca and alk levels :

Correcting you Ca and Alk levels

best to you, cheers.

[shoelevy]

hi, I wonder... if there are reef keeping publications that show that Mg causes dKh to be low.  I've been trying to find for such articles.  From my 'limited' understanding/reading... it doesn't.  Alkalinity drops are more likely due to other factors OR a combination of  them rather that solely due to Mg ... the thing is I don't think (I may be wrong here) tt Mg has even a remote connection to dKH as what some of you here say it is.

As most here would know that Alkalinity is dKH(another measure) and in this article : Alkalinity it was pointed that bicarbonate make up 89.6%, while carbonates 6.7%.  Thats a total of 96.5%, leaving the rest to a few others... there was an item called magnesium monohydroxylate, whose "Relative Contribution To Alkalinity" is only 0.1% !!

I think I've read somewhere of the direct relation of Mg to calcification of corals, however thats not what this topic is.

junyong84,

You'll best appreciate this hobby if you understand/find out why your dkh drops(as it always will). A dKH of 7 is not as dangerously low as its possible effect on your pH. ie. a low dKh can allow wild swings of your pH which can harm your LS. This article show how to correct your ca and alk levels : 

Correcting you Ca and Alk levels

best to you, cheers.

an article for you to read on the effects of low Mg on Ca and kh in reef tanks

http://www.advancedaquarist.com/issues/oct2003/chem.htm

relevant read is in one of the last section

as to y kh drops, because HCO3 and CO3 ions which is wat kh measures are consumed when corals build skeletons and when acidic materials are introduced into the system.

[madmac]

Thx shoelevy. I'm beginning to understand where all this talk about Mg affecting Alk levels come from now. The point made, in the last part of the article, is that with low levels of Mg, rapid precipitation of calcium carbonate crystals comes about. This takes up both Ca and carbonates ions resulting in diminished levels. Conversely with higher levels of Mg present, the rate of precipitation is delayed, resulting in elevated levels of Ca and Alk in the water.

Thats quite a valid point... as Mg is shown to have some direct impact on the calcification of organisms as well as the prevention of abiotic precipitation of CaCO3. It affects both, never singly and it would be certainly something worth watching out for. Thx.

mm

[AlfaRomeo]

MM, glad you approve of the article.

[madmac]

LOL, Alpha, that was the same article I read before about the role of Mg on the calcification of corals... I don't know how I missed out the later portion on its other dual role, ie preventing precipitation of CaCO3... its an eye opener for me, as I don't test Mg levels, I don't even dose Mg... to me its abundantly available naturally in SW, hence a small fall won't do much harm.

I also read here of the difficulty some hobbyist had to go thru to raise Mg levels. I'd like to keep things as simple as possible when it comes to maintenance. (tho, I'm truly awed whenever I come across snippets about your setup... its amazing what some reefers will go thru', the passion astounds me! /complement)

Personally, its not a real big problem unless Mg levels go to levels like closer to 200,... I think anywhere around 800 would still fine... this is no endorsement... it would always be better to keep as close to optimum where possible. I'll be getting an Mg kit for sure this weekend.

[AlfaRomeo]

MM, you cannot let the MG level drop below 1100 or you will have issues with unsustainable KH levels no more how much kh powder thingies you add. Try to maintain it at least at the 1200 level. This is form my personal experienced of course and not scientific in anyway!

Ionic imbalance can be resolved by first making sure Mg is at 1200 at a minimum, then adjust KH to at least 7 and then adjust CA to at least 400. then a properly tuned CR will help to maintain all the above at that level without regular intervention 10-15% of MG granules in the CR will help with the maintenance of the MG levels too.

As for my setup, Im aiming for less and less daily/weekly maintenance and I hope I am getting to that point soon where I only have to clean the glass weekly and the rest of the stuff takes care of itself without regular intervention from me. Makes my life a bit easier! *fingers crossed*

Cheers!