Alkalinity consumption rate
 

It turns out I've been dosing my two part chems all wrong for like the last year and a half. I'm an idiot, and it's probably responsible for a fair portion of the issues I've had (a coral killing home renovation not withstanding).

Anyway, I've fixed it, and since then my corals have just taken off. Not surprisingly, my consumption rate of chems has also taken off.

Since I clearly have no idea what I'm doing 7 years in to this, I just want to get a barometer for how much others who are using a 2 part recipe are dosing. I'm using Tropic Marin's 2 part, and I *think* they use sodium bicarbonate (though it might be soda ash), and through the magic of grade 10 stoichiometry I've figured out that I'm adding roughly 45.36 g of the stuff to my tank every day, and seeing as my dKH fell 1.01 in the last 48 hours that's not enough.

It seemed like a lot, because when you mix it up in to solution at Tropic Marin's recommended concentration that works out to 540 ml/day, but now that I've equated that back to dry weight it really doesn't seem like that much to me considering how many large SPS corals I have. One of the glass vials from a hanna checker weighs 11 grams empty with no lid.

I've followed the problems that you've had over the last year and a half and im curious what you mean when you say that you have been dosing your two part chems all wrong ?

I just buy Arm & Hammer baking soda at Costco and bake it in the oven at 350 for an hour - this turns it from sodium bicarbonate to sodium carbonate (AKA soda ash) which is an advantage if you need to raise your PH level, otherwise you can just mix the baking soda. Be sure to pour it into the water and not add the water to the baking soda or it doesn't mix well. Making your own 2 part would likely save you some $$$. If you have any questions about 2 part dosing give me a call - I have been dosing my own home made 2 part (Randy Holmes Farley's recipe) for almost 10 years.

My daily usage on Sodium bicarb is presently 128grams/day. I've been making some system changes so corals are still adapting hence growth rate is not what it normally is.

Something I have wondered about is if the chemically produced(Solvay/Ammonia Soda Method) Sodium bicarb absorbs residues from the processing equipment(metal piping and towers) and how much ammonia it retains.

Another concern I have is if you leave Sodium bicarb in your fridge it acts as a deodorizer. Does the Sodium bicarb sitting on the shelf with the other cleaners and chemicals absorb what they are off gassing?

Those two concerns are why I use(and sell) Natural source, water extracted, aluminum free USP #1 grade Sodium bicarb.

Cheers,
Tim

Do you bake it all at once after you buy it, or only a portion when you are ready to mix your solution?

I used to use the Seachem Reef Buffer (expensive) and have recently switched to bi carb (from Tim). But if it raises PH after baking, maybe I should do that?

Ugh, I'm ashamed to admit it. I was dosing unequal amounts of a 'balanced' supplement. I didn't realize just how unequal it had gotten, but by three weeks ago I was dosing almost exactly 2x the alk as calcium. Which means I was also dosing 2x the amount of sodium.

Why you ask? Because I'm a moron and forgot something I thought I knew like the back of my hand 5 years ago

Not sure if that contributed to anything, but my tank would always drastically improve after a few large water changes in a row. Since I fixed it, things that haven't grown in a year are growing and a problem I was having with Acropora hyperplasia has started to resolve itself. I think I'm also now seeing my tank's "real" consumption rate,

I used to use baking soda, but even when mixing with DI water, I'd get this weird chalky precipitate at the bottom of the container. The tropic Marin stuff doesn't do that. It is expensive, however, and if Tim considers 128 grams/day low, I might have to switch.

Tropic Marin recommends dissolving 420 grams of the alk and 380 grams of the calcium in 5 L of water. At 540 mL a day and rising, I'm burning through my 3 gallon dosing containers pretty fast. How much do you think I could increase the concentration of each without risking supersaturation precipitation?

assuming you're mixing a solution, from RHF 2 part guide

http://i67.photobucket.com/albums/h3...psxty6tlbk.jpg

Yeah well we all make mistakes sometimes.

This does illustrate the major flaw in the so called "balanced" system.
Maybe this applies in a lab, but definitely not in real life.
And certainly not on an sps system, as anyone that has successfully kept an acro tank knows this.



I use the Fauna Balling system for my alk, and i have will switch to a USP grade #1 alk from time to time.

Our sps system has a consumption rate of around 253 grams per day,
but this is based on 3 x 4' x 8' coral beds full of sps and with regular and large WC's.
WC's are replenishing alk
Corals coming in and out disrupt stability which decreases consumption…
So basically my data is useless for you, but still :)

Keep dosing and keep testing till your tank is stable.
And once it seems to stabilize don't stop testing.
You will seem to reach a balanced point.
then your sps will basically go "hey this is freakin perfect growing condition"
And your consumption rate will skyrocket again.
Then once you balance out you will be tuned in.

A drop of 1 dKh in a day…. yeah thats not good for happy sps at all…
Personally i like to keep my alk swings below .5dKh per day, up or down.
So don't raise it to fast either, but make sure it doesn't go to low either (yes i know, kinda hard to do.

That might be because either your trying to mix too much bicarb into the amount of water or the water is cooling too much after dissolving and the bicarb won't stay in solution. I find it works better if you warm the water to about 80°f. I mix at a concentration of 86 grams sodium bicarb to 1 litre of water. I stir it for 15 minutes to make sure it's all dissolved.

Hmm.. very cool tip Tim, I will try this.
I have found the precipitation from sodium bicarb too and i just don't use the bottom tiny bit of the container.
But i will definitely try this!

Gah. Dkh fell another 0.89 in the last 24 hours. I don't think I'm being aggressive enough enough with my rate of increase. I jumped the rate by 120 mL/day and readjusted the level manually. It took nearly 2 full cups to brink alk back to where it was yesterday, which is like 470 mL, but I'm too chicken to increase my dosing rate that much in a single day. I'll be upping the rate again every day this week until it stops falling.

Those dinner plate sized monti-caps are beasts.

When corals start growing quickly, especially monti's they can consume a lot of alk.

A few things to check.
Make sure your heater and the magnets on pumps are not encrusting calcium. Also check to make sure any sand is not doing it either.
Check your Magnesium, should be 3x calcium or 1350 to 1450. To low of a magnesium will cause calcium to bind to heaters, magnets, glass etc.

Cheers,
Tim

I (very) briefly considered switching to dosing today. I read this thread, changed my mind :)

You, with a calcium reactor ?
Why would you switch back ? If I'd started with a reactor it would have saved me SO much grief

I'm regretting choosing dosing, but was told to start with it and switch later if I need to :surprise:

More just a logistics thing with equipment placement, and fighting high alk at the moment :) I have to build a second cabinet to house my reactor out of kid's reach, and had a lazy moment lol. Dosing would fit under my stand. No real good reason other than that.

As well Coraline algae will use up a large demand if there is enough of it in the system and is often a major consumer :)

Most people are shocked by the dry weight they need to add daily with Alk , more often than not people are afraid to add the amounts they should and end up slowly watching it drop and then play catch up slowly to bring it back with a doser :)

Good luck Adam you'll get it :)

I had an experience with high co2 consumption with my reactor before I shut it down. Turned out the pressure regulator was leaking CO2. A large 5' bottle only lasted 2 months. LoL. Glad it was in the shop and not my house.

Tim, I emptied a 20# bottle in 24 hours in my livingroom. Nobody died :)

I didn't have space for a calcium reactor when I set up the tank, but if this is headed where it seems like, I'll be going through an entire $24 box of both tropic Marin's part A and B every 8 days. I'll probably go back to bulk chems before I get a calcium reactor, but I got rid of my external return pump a while back and have a big empty space next to my sump...

Also, I've been very concerned about the possibility of precipitation. But there's none. Not on any pumps, heaters, nothing. The amount in dosing right now can barely keep my dKH over 7 and my calcium hovering in the 390s, neither level is high enough to indicate precipitation could be occurring

But did they get a buzz? ;)

I think it's kind of funny (cute?) when people start dosing, and they say "I dose more and more and I can't keep up." Just keep dosing more. As your parameters stabilize the growth will increase too, so then you'll be behind again. By now you should have a good idea how much you increase the dosing and how much that affects your numbers. Just keeping increasing until you find the happy spot, but continue weekly testing until your tank is full (of corals) and the increase in consumption is less. A growing tank will always have a greater and greater demand until you're fragging just as much as is growing. I can't remember if you mentioned magnesium at all? You're testing that as well, right? You're in the 1300-1400 ppm range?

I do this too, except I use a MJ400 to do the mixing. Using warm water makes a big difference when mixing sodium (bi)carbonate.

Regarding any precipitate at the bottom of the container - I do get some but I really don't worry about it. I draw the solution through an air stone so I don't clog up my hoses or pumps. I also run a small powerhead in the alk tank to help things stay in solution.

That's interesting about the precipitate from the alkalinity solution. I don't get any precipitate from either Fauna Marin or Tropic Marin. TM mixes a lot easier than FM for some reason, but they both dissolve completely.

i mix alk in about as hot water as i can get and i mix calcium in about as cold water as i can get lol :P

I've been testing my alk daily, my calcium every few days and magnesium once ever 7-10ish days. More because of the time it takes to do each test than anything.

Magnesium has been steady at 3x calcium, which since calcium has been low has been in the mid 1200s for a while, I'll do some more rigorous testing this weekend and make sure they're all still in balance. I've been using part C from Tropic Marin's system as well, I suppose your'e supposed to dose an equal amount of part C as parts A and B, but even with barely dosing my magnesium doesn't change much, so I'm not sure if I'm ready to do that.

well after dosing 780mL/day of Parts A & B my dKH only fell by 0.3 in 24 hours, so I'm getting there. Just re-adjusted manually and upped the dosing rate by another 120 mL/day.

gah. I want a calcium reactor!

WOOHOO! 900mL/day is the sweet spot. dKH up 0.06, which considering the margin of error on the hanna checker and the slight variances expected measuring 10 mL of solution and 1mL of reagent without a micro-pipette, it's basically the same as yesterday.

Damn. Is that normal for a tank that size? I think I need more coral. I only use 12ml a day. :sad:

I wonder how many mls/day you'd be using if you were running 2-part ?

I'm currently using 100mls/day of alk in my 75g with a less than medium stocked level of SPS

I don't know, I've never had to dose this much before - but I've also never had a single tank for this long, or a tank this size, or this many corals either, so I don't really have a bench mark to compare 'normal' against.

However, I have a lot of montipora from at least 4 different species. It grows incredibly fast, and the bigger it gets, the fast it grows. A few of them have super designs skeletons, so sitting here looking at it I can imagine that much calcium carbonate getting laid down all over the place bit by bit every day.