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Brockly
08/21/2017, 12:27 PM
So I have some newby 2 part dosing questions for anyone that can clear this mud up please

I am trying to maintain a DKH of about 9.5 (reasoning = seawater is high 8s my RSCP salt is about 12 so I figured shoot for middle so 9.5 ish)

first is that even advisable, or should I maintain 12 since my salt is 12, not sure about how I feel about that.

main topic.
My system is 100 gallons total volume (75 tank 25 sump)
I have about 50 lbs reel reef rock, 1-2 inches sand, 2 marine pure bricks for added bioload. I run an old euroreef skimmer, and a chateo media reactor. I was running gfo/carbon but took it offline for now since tank was running very clean. The tank is only 4 months old so pretty new yet, but everything has settled in. I plan to run a mixed reef. Right now I have 5 fish, about 20 coral frags. about 3rd 3rd 3rd coral. Mostly zoanthid, few favia, few montis few acros. Everything is just startign to grow but nothing crazy yet.

I have been dosing 50ml per day of BRS 2 part ( calcium chloride and soda ash) with a dosing pump. for about a month and the alkalinity was slowing going down. I increased it to 70ml per day and the levels were a bit more stable. of course I would want a rock solid on moving alk level. But can't seem to manage that. it seams to fluctuate when I test. I use a hanna checker for testing. seams to always be between 8.5 and 9.5 Ive seen up to 10.3 before. Is that aceptable fluctuation? It doesnt stay solid.


3rd random question, is I stopped doesing for 2 days to see the consumption and it went form 8.7 to 8.1 down .6 DK in two days, so lets say .3 per day.

BRS calculators say to rise .3 it is 21ml does. But I am doesing 70 ml which is 1 dkh dose amount for 100 gallons. Im all weirded out by the numbers not adding up.

RobZilla04
08/21/2017, 12:57 PM
So 9.5 might be a little high but okay. 12 dKH is definitely high IMO. You can switch to a salt mix which will better mirror your parameters (Alk, Cal, & Mag). Chart on this page http://www.thatpetplace.com/salt-mix-guide

Second the Hanna checkers do tend to give a small fluctuation even when tested back to back. A small range, .5 or so, shouldn't worry you.

Dosing gave me headaches for a while to. I was nervous to over do it. You're going about it the smart way, meaning you're under dosing to start with and slowly bringing the volume up to match consumption.

Keep an eye on Cal as well. If you are adding that much Alk, I'd be concerned with Cal falling too far. Mag should be monitored as well. You may get to a point where you need to dose all three, with mag being the lowest volume.

This article helped me understand the relationship between Alk and Cal.

http://www.advancedaquarist.com/2002/11/chemistry

Brockly
08/21/2017, 12:58 PM
Oh forgot PH my ph is rock solid at 8.3, never moves from that. I use saliferts test, and that is the reading from what I can tell. 8.2-8.3 not sure but the color is always the same.

Brockly
08/21/2017, 01:03 PM
So for clarification I do dose magnesium as well. 5ml ever 4 days. just a random small number then when I test for it I increase or decrease the does.

my calcium is at 430 and magnesium is 1430 at the moment

I always does equal parts of 2 part, some say to customize the 2, but most say always equal.

mcgyvr
08/21/2017, 01:07 PM
You need to be able to get consistent test results before doing anything..
If you can't do that you are SOL..
The test kits should be accurate enough.. your tank shouldn't fluctuate wildly though as you seem to be saying it is..

How often and how much water are you changing? That alone could be the reason for the fluctuation you are seeing..

Note: that you certainly do NOT have to dose equal parts of the cal/alk mixtures.. It seems to be pretty darn rare to need to also..Make sure you are testing both cal/alk and dosing accordingly which probably won't be equally..

Also.. have you checked mag? If mag is out of wack then you can have weird problems as its basically the "stabilizer" in the mix.. get it right before you do anything else..

RobZilla04
08/21/2017, 01:13 PM
So for clarification I do dose magnesium as well. 5ml ever 4 days. just a random small number then when I test for it I increase or decrease the does.

my calcium is at 430 and magnesium is 1430 at the moment

I always does equal parts of 2 part, some say to customize the 2, but most say always equal.

I've heard both sides of the argument as well; equal parts vs. custom based on consumption.

Mcgyvr is right, you need solid numbers before you start playing around with the dosing.

I suggest you stop dosing. Wait a few days, do a large WC, wait a few hours and test Alk Cal & Mag. Then wait several days and test again. Calculate consumption and base dosing volumes on the consumption rate for each (Alk, Cal, & Mag).

Brockly
08/21/2017, 01:49 PM
You need to be able to get consistent test results before doing anything..

How often and how much water are you changing? That alone could be the reason for the fluctuation you are seeing..
.

I was doing 25 gallon water changes so 25% around once a month. I haven't done any water changes for the last month to eliminate that as a factor. In th ebeginning it was a huge variable for sure

so for cleaner commenting data in the past few days I had

august 13th
410 calcium
9.3 dkh
1365 mag (did a boost to get it above 1400)

august 19th
430 calcium
8.7 dkh
1430 mag

I dosed 70ml of both calcium and alk each day with no water changes. so to me the balance seams alright, just maybe needed to does a bit more alkalinity.


then I took all dosing offline for 2 days just to monitor consumption and I thought it was odd that dkh only dropped 0.6 that is only like a 40ml dosing drop. when I was previously going down when dosing above that?

Martin Kuhn
08/21/2017, 02:10 PM
Once Alk goes down in a suboptimal range, also consumption gets less.
Once you see a 0.5 to 1.0 consumption and you can trust your measurements, measuring only 1 day would be better.

For tanks with adequate 2/3 part dosing, "normal" salt mixes are more adequate than "pro - reef" mixtures. They're closer to the Ca/Alk/Mg values you are aiming for

There are several more or less trustable lists of measurements of salt mixtures.
I measured lots of mixtures by myself, always with the same equipment. You find the results either in AquaCalculator or also in my waterparameter FAQ.

Anyhow "pro - reef" mixtures are better for tanks where no dosing is done. So they can keep up the parameters in tanks where the consumption is not as high.


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bertoni
08/21/2017, 03:08 PM
9.5 dKH is a reasonable target for alkalinity, although the ocean runs more like 6.5 or so:

http://reefkeeping.com/issues/2005-11/rhf/index.php

The consumption rate of the two supplement should be very close to equal in most cases, although there are a few processes that can change that:

http://reefkeeping.com/issues/2004-12/rhf/index.htm

I'm not sure how repeatable the Hanna Checker is in practice, but it should be close enough for our purposes. Staying in a 1 dKH is stable enough, in my opinion. The higher excursion you noted likely is okay, too. Water changes can change the results, as has been noted. I might switch to a salt that is okay out of the box or can be dosed to where you want the parameters, but Red Sea Coral Pro is fine.

Sometimes, dosing regimes cause a lot of precipitation of the supplements. That can happen when dosing into a small volume of water or if the dose is a bit too rapid. If there are signs of tannish or whitish buildups on the walls or inside pumps, I'd consider looking into changing the dosing a bit. Other than that, I think your setup is fine as is.

Brockly
08/21/2017, 03:20 PM
thanks Bertoni, Good to know. When I first started the doser 3 months ago I had a precipitation problem for sure. Since then I now spread the does out to 10 doses per day of each spaced 1 hour apart . so for example 8am 7ml calcium, 9 am 7 ml alk etc. so it takes 20 hours to dose every day.

I does into my return chamber that is about 9 gallons and added a powerhead there to make the flow and surface ripple like crazy to make sure it instantly merges with the water.

Good to know Im not crazy and will just keep at it. I just hear people say they have unflinching alkalinity. And I wonder how unflinching that actually means. If .5-1 dkh a day is acceptable, then I am well within that I guess. thanks for the input. I just swapped to RSCP salt after everyone says how awesome it is, after years with IO. But I might swap to something that else, we will see. I jut got sick of how low IO magnesium was.