High DKH

[robalv]

I have constantly had a dkh reading of 15 to 16 evrytime I test. Before lights out , mid day , after lights on have not tested water from lfs as 8 have purchased a ro/di unit and that has test at trace. Anyway my question is after water changes 15 gal weekly on my total 150 gal with sump with no changes, I would like to see if anyone has any suggestions on what to do?. I want to try Muratic Acid...... I know scary but has anyone tried this befor? Any help will be awsome.

Please only reply with usefull information.

Thank you in advance
Rob.

[Europhyllia]

what's your pH like? Are you buffering?

[robalv]

Ph is 8.3 no buffer. I am dosing seachem 2 part but even before it was 15/16 dkh. I stopped kalk as well.

[robalv]

Anyone know how to go back to the standard version of maast I don't like the mobile version.

[Europhyllia]

bottom of the screen. drop down menu on the bottom left :)

[lt1z28]

What brand of test kit are you using?

[robalv]

Does not have it

[StevenSeas]

what salt mix are you using? have you tested the new saltwater before being added to your tank? I know some salts have higher/different values than others. Also if this isnt the cause I wouldnt worry about it 15 is a little on the high side yes but better stable than swinging. If you try something like the acid to drop it your going to through off your buffering capacity (yes I know thats what you want to do, lower it) but this also will allow for more of a pH swing at nights and will just throw everything outta wack imo. What is your calcium levels? mag if possible? We did an experiment in lab about buffers and pH which is what dkh has to do w/ (measure of buffering capacity) Basically a buffer system in this application would be a base with its conjugate acid in solution. When an acid is added the base grabs the H off of the acid to neutralize it and keep the pH at 8.3. When an base is added the conjugate acid gives a proton (H) to the base and thus the pH stays at 8.3 (or whatever your pH is at.) the dkh readings that we get is to the best of my knowledge just a measure of the amount of conjugate acid/base is in the system and therefore the amt of outside acid/base can be added to the system before a significant change in pH. So the idea of adding the Muratic Acid imo would be a bad solution as it would eat away all of your buffer (the base can only take up so many protons (H)) and once that is done your pH will drop quite drastically. So that being said if you happen to add too much it will most likely have very bad side effects. My guess is its from your salt mix and if you really find an issue with too much dkh research different salt mixes that make up water with different dkhs

[robalv]

Dang steve can you type in lamens terms geesh.... I am using the seachem salinity ....if that helps you any.. all I asked is if someome has tried this before and had it work for them. I know as stated before the conns on this. I tried your recommended water changes with no real progress. Thank you.

[StevenSeas]

ya i will retype it up after class (hockey yay) but wouldnt recommend this unless you have a pH probe and did it over a long course of time

[StevenSeas]

Hey Rob do you run anything like a calc reactor? what kinda substrate do you have? livestock?

[acropoorer]

Rob, two part is a buffer and calcium, quit using the buffer part (alk). If your calcium is ok, don't add that either. Over time your KH will fall, how fast will depend a big part upon how heavily stocked your tank is. For example if you have wall to wall acros it will be fast, if you have just a handful of small stonies it will be slower but it will fall. I assume you don't run a calcium reactor as you said you are dosing two part.

After your kH has fallen to say, 10 or 11, slowly start back with the Buffer, but monitor KH till you have tuned the buffer dose for your tank. Personally, I like to run KH in the 10-12 range as I grow a lot of stonies and low KH is much worse than high for SPS.

[StevenSeas]

OK here ill try to break this down as to why I personally wouldnt ever do this or advocate this. Ok so dkh or alkalinity is a measure of a tanks buffering capacity. A buffer is something that will auto correct a change in the system. In marine systems our buffers come from bicarbonate. This happens to be what sand/rock/and mostly crushed coral give off to the system a natural buffer system if you will (its how the ocean does it.) pH is a measure of the "power of hydrogen" and acid is more Hydrogen and basic is less Hydrogen. So acids have an excess of Hydrogen and they "donate" them to base which is lacking in Hydrogen. Bicarbonate is a base and when it gets a Hydrogen from the organic acids from fish poop and urine it turns in to an acid because now it has an extra Hydrogen. This is called it conjugate acid because its the same molecule but with an extra proton. So the next time a base is made in your tank the bicarbonate+H (conjugate acid) donates the Hydrogen to the base to neutralize it. The Bicarbonate system centers around 8.2-8.4 so the ideal pH range for saltwater (b/c its that way in the ocean.) So the problem that occurs with purposefully adding acid to a tank is that it donates all their extra Hydrogens the Bicarbonate which then become acidic. This isnt really the problem. The problem is 2 fold:
one if too much acid is added there wont be any more of the basic version of Bicarbonate in your system which will cause the rapid decline in pH.
This graph doesnt fit this exact situation but its as close as i could get. If it was flipped upside down it would be prefect. Change the 3.3 (roughly the start) to 8.3. As the volume of acid added is slowly increase the pH slowly changes until all of a sudden a drastic change occurs (the near vert line on the graph) this is a really quick change in pH that would drop it to roughly the acidity of the acid being added.
http://www.shep.net/resources/curricular/Physics_Denis/Caffeine/images/acidbase.gif

One ml too much added and you just hit the "magic point" where the pH changes rapidly. So without a pH probe and a lot of time to slowly add the acid i wouldnt do this.
The other reason I wouldnt perform this method is that the dkh would be lowered b/c the change in bicarbonate however once a base is added all that bicarbonate was changed into bicarbonate+H is now bicarbonate again and you are back to where you started with a high dkh and and in order to get there a rapid increase in the pH.
just my thoughts on the subject. I would leave the high dkh alone unless it really bugs you that you are 4 degrees above what is the normal dkh of the ocean. If you are experiencing good growth as is then keep it stable imo. Also if you have a lot of crushed coral in your system and your high dkh really bothers you that much remove some of it SLOWLY. Sand/crushed coral/LRR/LR all add to the bicarbonate in the system because this is how the ocean naturally buffers its water so we get it as a side effect of having these in our systems. Crushed coral ime and imo is the largest contributor to it. (There is a really good article out there about it and how making artificial reefs and then killing reefs create bicarbonate which leads to the increasing pH in the ocean.)
Your salt isnt to blame here as Sea Chem Salinity salt is tested for quality in every batch and the sats of max and min for each component for the specific batch are posted on the side of each bucket for that batch. Sea Chem has their salt at 10.75 on avg.
If you need anything else explain lmk

[BIGBIRD123]

You guys are trying to make this into a job...too technical. Rob do what Dale told you. I would not try the acid method...it will go done in time. Mine stays near 14 and my corals are fine.

[StevenSeas]

+1 to BIGBIRD I agree it will be gone in time and to just let it be. I too have yet to see ill effects of a dkh in that range

[BIGBIRD123]

Steven, not trying to rain on your parade and great to see someone with the technical aspects but most of us don't understand all that and would probably kill our tank because of it. :)

[StevenSeas]

lol know I understand. However relating my chem and organic chem to my tank is the only way to help make it make sense to me so I can pass the stupid classes. I was just tryin to point out as to why not to do it, heck if i wasnt in o-chem right now i wouldnt have understood a lot of that but tried to break it down best I could. Hopefully this doesnt cause anybodys tank to crash. But to me I love the technical side b/c I have to know how it works in order for me to understand it

[BIGBIRD123]

Yea, I know. I'm just from the old school. No offense intended but I would take experience over education any day. In my 35 yrs of Construction, experience got more done....lol

[robalv]

hey thanks guys I am home now, hard to read my phone and drive and type back... I was using Seachem Reef Fusion 1 & 2. No I am not running a Calcium Reactor and will stop dosing today... I was told to use both parts to try to control the problem.... I have 7 colonies a few frags of Sps ,2 clams and a few Pallys , Zoas and 13 fish... everything looks great just want to get a handle on things.. I just picked up a Octopus Extreme 200 thanks Brewercm. Stopped the Kalk... I have not done a water change in 2 weeks this coming Sunday usually do 15 gal. total 150 ish with sump, can I or should I do a 40% water change anytime soon? Also my substrate is black reef sand, I know but I thought it was a good move in the beginning, I am wanting to add crushed coral and remove most if not all the black sand a bit at a time, suck it up while doing the water changes.. let me know what you think..

Thanks again

Rob.

[StevenSeas]

can you yes but for what benefit??

[robalv]

Yea, I know. I'm just from the old school. No offense intended but I would take experience over education any day. In my 35 yrs of Construction, experience got more done....lol

F N A MAN...

[StevenSeas]

remember the adage "if it aint broke dont fix it" if your tank is happy and everything is growing dont do anything out of the ordinary imo

[robalv]

reflect the light back up instead of absorbing it.

[StevenSeas]

reflect the light back up instead of absorbing it.
huh?

[robalv]

can you yes but for what benefit??

reflect the light back up instead of absorbing it.

[StevenSeas]

ahh i replied to your post when you had yet to say anything about changing out the substrate but just doing a 40% water change. I was like huh how does a water change effect the light being absorbed or reflected ?!?!? LOL