Alk/Ca balance and pH drop

[MrAnderson]

oh cmon L34NN3 don't be like that, you know how it is in forums like this.

 

look, there's a lot of confusion in this hobby when it comes to chemistry, and multiple approaches that will work. it's all about what your goal is - whether you want stuff to thrive, whether you want to have the "ideal" arbitrary values for certain params, whether you want low maintainance, etc. the methods for each of these don't always overlap.

 

so take it easy and come back. to be fair, you ARE getting a little to active about chasing numbers, but we've all been there at one point or another. but you also are getting some good advice in this thread (not only from me lol). so stick around and reflect on the complexities of seawater chemistry and take some time to learn more about it - blood chemistry is a lot simpler to be honest because the environment is largely self-regulating. with your reef, YOU are the one controlling homeostasis. you're smart so i'm sure you'll be an expert soon enough, but it's ok to not get it all at once, just like anything else.

 

so here:

 

 

we cool?

[Sexy Shrimp]

Aw I got flowers off Mr A... Can I have a group hug too?

[bdare]

[Sexy Shrimp]

Awww feel all warm and glowing now

[Mark S]

I dont think you were getting jumped on, it just seemed you had low alk then high alk from over dosing or something. Overeacting to a minor ALK problem is all. Just set you ALK at a normal number like 9 and let the CA come to it...it will slowly over time. It is NOT necessary to have perfectly balanced water all at once. Masterbuilder has a point, dose a small amount and wait. Dont test so much, enjoy your tank. Its much better, IMO to have parameters at are off some than to be messing with it all the time.

 

My tank is doing just fine and has for almost 2 years... I dose for ALK only two times a week. as long as it between a low of 8 and a high of 10, I am happy. I dont even have a PH kit anymore.

 

We love ya here, we just hope you can relax and be happy with your nice tank.

 

You scientist types would drive a wooden Indian crazy

Thats funny

[The Propagator]

"Wut choo tawkin' bout Willis"?

 

What's wrong with RC?

 

Yeah I edited that out after rereading what I had thought I read while you were posting that skippy. Its not reefcrystals in general but its a specific brand of reefcrystals.

 

 

 

Answer my question Leanne Or I am flying across the pond with my test kit and yellow tights!

[Sexy Shrimp]

There's nothing wrong with RC. That's what I use. It mixes with an alk of 12 and Ca 460 at 1.025 sg

[Sexy Shrimp]

Well I have left my tank alone for a while with nothing but water changes and here is what happened..

 

KH - 6

Mg - 960

Ca - 440

pH - 7.8

 

Grrr

 

Here's what I did. I dosed for Mg and KH using this online chemistry calculator and the levels came out at

 

KH - 10

Mg - 1340

Ca - 440

pH 8.0

 

Did a 30% WC as I used epsom salts and then left the tank for 3 days. I had a massive coraline spurt (whacking the Mg up really had an effect!) and it resulted in the following:

 

Levels before and after:

 

Mg 1360 - 1220

KH 10 - 6.25

Ca 440 - 380

 

My calcium is always really stable - it must be because the Mg was too low for the corals to utilise much of it. The Calcium is now starting to get used - woo hoo!

 

So in 3 days my levels have dropped by

 

Mg - 140

KH - 3.75

Ca - 60

 

I did a water change and tested again to see how much a water change brings the levels up and calculated my daily dosage from there...

 

After water change

 

Before - 3 days - Water change

 

Mg 1360 - 1200 - 1180

KH 10 - 6 - 7

Ca 440 - 380 - 420

 

So basically every water change I was doing previous I was proportionally depleting my Mg in relation to my calcium...

 

From this I have calculated my daily dosage to be 1tsp CaCl2, 1/4 tsp baked baking soda (or 1/3 tsp baked - depending on the pH) and 24g Epsom salts (which seems quite a lot!).

 

I have made one batch to top up the current levels based on parameters after the water change and have also made up enough top up water with the above in to last for 3 days (of top ups and dosing). I will test again and see how it has worked after a week of dosing this amount.

 

Now for a question: I have Added enough of the initial dosage to bring the pH up from 8.0 - 8.2. Should I have made some up with unbaked too or will I be able to continue adding the baked without changing the pH too much?

 

EDIT - for all of you who will say I am chasing my tail again; I have tried to be systematic so I can calculate it once and then just add the dosage to my daily maintenance (to avoid chasing my tail ). We'll see whether this has worked in a week

[bdare]

Here are my thoughts:

 

1) The effect of the spike / drop in Ph after dosing the alk portion is temporary. Your tank will recover within 10-15 minutes so don't worry about which you should use. I tend to use the baked in my dosing pump and the unbaked when I need to make adjustments to keep precipitation at a minimum.

 

2) It always takes A LOT of Mg supplement to increase Mg. Be careful about JUST using epson salts for the Mg portion. This is not a balanced additive which is why Dr. Randy Holmes-Farley uses Mg Chloride and Sulfate in his recipie. Keep an eye on your SG as the salt in the Mg will cause your SG to raise.

 

3) I think we've discussed this before, but what salt are you using and what SG are you mixing it too? Sure seems like a BIG drop in your params from just doing water changes.

 

Otherwise... it looks like you've worked out a good scenario that works for you. Glad to see things are smoothing out for you!

[Sexy Shrimp]

Here are my thoughts:

 

1) The effect of the spike / drop in Ph after dosing the alk portion is temporary. Your tank will recover within 10-15 minutes so don't worry about which you should use. I tend to use the baked in my dosing pump and the unbaked when I need to make adjustments to keep precipitation at a minimum.

 

That's good to know - I didn't know that baked precipitated (learn something new every day eh?)

 

2) It always takes A LOT of Mg supplement to increase Mg. Be careful about JUST using epson salts for the Mg portion. This is not a balanced additive which is why Dr. Randy Holmes-Farley uses Mg Chloride and Sulfate in his recipie. Keep an eye on your SG as the salt in the Mg will cause your SG to raise.

 

I hadn't thought of this either - I am so glad you stopped by!

 

3) I think we've discussed this before, but what salt are you using and what SG are you mixing it too? Sure seems like a BIG drop in your params from just doing water changes.

 

W/C, coral and major coraline. You would not believe how much coraline had increased in just 3 days, and my corals are growing away like wildfire too... I am was using Reef Crystals but have just switched to Red Sea Coral Pro (discounted and a free t-shirt). I mix to 1.025 SG so it should be higher than they quote (think they quote mixing at 1.021).

 

Otherwise... it looks like you've worked out a good scenario that works for you. Glad to see things are smoothing out for you!

 

Thankyou again Bdare. The tank is really blooming now (and making me money selling frags!). Since dosing my mushrooms have gotten absoluetly huge!

 

Before (excuse the grubby, mid w/c water )

 

 

After (compare to the size of the ric...) excuse the poor photoshopping - the images were really dark

 

[bdare]

The baked doesn't necessarily precipitate out on its own, but it does cause a spike in Ph and precipitation is more likely in higher Ph.

 

If you are mixing to 1.026 you should check the params of the water you are adding. At 1.026 I can't imagine there are many salts that should bring you down that low.

[Sexy Shrimp]

I don't think it is the salt that is bringing me down (apart from the Mg) I think it is just that my corals are growing really quickly and my coraline is going bananas...

 

The Mg didn't actually "fall" with the water change but was proportionally less compared to the calcium. My test kit is combined Mg/Ca and Ca. You have to subtract the Ca from the combined to get the Mg - it doesn't take much of a rise in calcium to drop the Mg (but is it really a drop?)

[PodRod]

Just read the last couple of pages and this sounds very familiar. I switched to Red Sea Coral Pro several month ago and had the same problems in my take. Sudden growth but params all over the board and VERY low Mg. I then switched to D-D H2Ocean, which has the same params as RSCP but with high Mg, and problem solved. Ca, Alk, Mg, and PH now all stable. Just a thought...

[Sexy Shrimp]

Good idea but I have only switched to Red Sea in the past couple of weeks and this has been a long standing problem (through 3 different types of salt). I think it is just through having so many hard corals in such small volume of water...