Water change not helping

[Fourevrloud]

Did a water change last night changed 20 gallons in my 92 gal tank
Before I did it my cal was 380 and dkh was 7
Checked it again tonight and it's the same.
Salt 1.026 with reef crystals so it really should be higher I would think
It's all lps and no clams any ideas thanks

 

[lnevo]

Time to start getting ready for dosing 2 part, kalkwasser or getting a calcium reactor.

 

[Fourevrloud]

Yea I thought someone was going to say that lol I just needed to make sure that's what the issue was

 

[lnevo]

Take a few measurements in a couple days and then a couple more, should give you a good idea your consumption. Also make sure your test kits arent expired and double check the results with a friend or lfs or another kit if you have. But yeah, i don't get high results from my RC salt either and frequently find my levels drop after water changes. Its also a good idea to test the new water to see what your starting with.

 

[duke62]

Try another test kit

 

[Fourevrloud]

Both great ideas thanks for the info

 

[evoIX_Reefer]

I just experienced the same issue. My alk is dropping even though I just did a water change last night. I didn't expect the minimal corals I have to consume that much alk so quickly. I am using RC salt as well and thought it would raise my levels.

I have my 2 part ordered already so waiting for it to arrive. Also, got another set of test kits for alk because it seems to be depleting a lot quicker.

I was sustaining it at 8.4dkh before the addition of a few LPSs.

Sorry to jack your thread but I figured to add since it seems like I am in the same boat.

my ca is 475
my mg is 1410
and my alk previously was running at a constant 8.4. Now down to 7~.

If I add just alk because of the higher levels of ca and mg, will it balance out CA and MG?

 

[Fourevrloud]

I just experienced the same issue. My alk is dropping even though I just did a water change last night. I didn't expect the minimal corals I have to consume that much alk so quickly. I am using RC salt as well and thought it would raise my levels.

I have my 2 part ordered already so waiting for it to arrive. Also, got another set of test kits for alk because it seems to be depleting a lot quicker.

I was sustaining it at 8.4dkh before the addition of a few LPSs.

Sorry to jack your thread but I figured to add since it seems like I am in the same boat.

my ca is 475
my mg is 1410
and my alk previously was running at a constant 8.4. Now down to 7~.

If I add just alk because of the higher levels of ca and mg, will it balance out CA and MG?

Don't be sorry at all all info is very helpful and I appreciate all and any feedback

 

[evoIX_Reefer]

Were you checking your parameters prior to the drop? Was it stable then a high degree of decrease in alk? Your calcium is on the low side of the proper range so what was your parameters before?

 

[Fourevrloud]

Cal was 400-420 alk was 9 prior then I added a couple big pieces of Lps and I noticed
A stunt in growth

 

[Nandez13]

I started dosing calcium since my API test kit was telling me my Ca was around 360. I then bought a Salifert test kit which told me my Ca was actually 420. In the meantime my alk levels dropped due to the calcium dosing and I lost a few corals. The cheaper test kit was throwing me off all along.

So, make sure you have reliable test kits and don't neglect your alk/mag levels either.

 

[sgdcover]

Always good to check your test kit once in a while with a friend or at a pet store. Just had that happen with a Salifert kit that suddenly stopped working.

BTW. Make sure you test your magnesium, that also affects both PH and dKH. Also, have you been dosing calcium and baking soda?

******
DISCLOSURE... this is something i've realized a while ago, but I may be wrong either COMPLETELY or just in the way I did a Math. I welcome any disagreement.
******

One thing to note too: doing a water change helps, but from true impact, you won't get much of a result from partial changes. If you think about it, to get any chemical level to where you want, you'd have to do a 100% water change. I suck at math, but I'll try this:

Parameters:
Calcium 100 (just for simplicity sake)
Desired Calcium: 200
Gallons 100
Water Change: 10%
New water has 200 Calcium

You do the water change, results:

10% of water has (ie 10 gallons) has 200 calcium
90 gallons has 100
Extra amount of Calcium is 100

You have to divide the newly added calcium by the TOTAL number of gallons of the tank, so:

100 Calcium divided by 100 = 1

You just increased your calcium by 1. Your new calcium level is 101. Not much of an improvement.

These are fake numbers, but it's just for demonstration purposes.

And, here's another thing, even if you do a 10% water change every day for 10 days, you'll still never reach the desired Calcium level because after the first water change, you start replacing new water.

 

[Fourevrloud]

I started dosing calcium since my API test kit was telling me my Ca was around 360. I then bought a Salifert test kit which told me my Ca was actually 420. In the meantime my alk levels dropped due to the calcium dosing and I lost a few corals. The cheaper test kit was throwing me off all along.

So, make sure you have reliable test kits and don't neglect your alk/mag levels either.

i am using the api kit im going right after work and getting salifert or red sea kit thank you

 

[Fourevrloud]

Always good to check your test kit once in a while with a friend or at a pet store. Just had that happen with a Salifert kit that suddenly stopped working.

BTW. Make sure you test your magnesium, that also affects both PH and dKH. Also, have you been dosing calcium and baking soda?

******
DISCLOSURE... this is something i've realized a while ago, but I may be wrong either COMPLETELY or just in the way I did a Math. I welcome any disagreement.
******

One thing to note too: doing a water change helps, but from true impact, you won't get much of a result from partial changes. If you think about it, to get any chemical level to where you want, you'd have to do a 100% water change. I suck at math, but I'll try this:

Parameters:
Calcium 100 (just for simplicity sake)
Desired Calcium: 200
Gallons 100
Water Change: 10%
New water has 200 Calcium

You do the water change, results:

10% of water has (ie 10 gallons) has 200 calcium
90 gallons has 100
Extra amount of Calcium is 100

You have to divide the newly added calcium by the TOTAL number of gallons of the tank, so:

100 Calcium divided by 100 = 1

You just increased your calcium by 1. Your new calcium level is 101. Not much of an improvement.

These are fake numbers, but it's just for demonstration purposes.

And, here's another thing, even if you do a 10% water change every day for 10 days, you'll still never reach the desired Calcium level because after the first water change, you start replacing new water.

thank you no i havent doesd anything yet

 

[sgdcover]

You'll have to dose, especially if your SPS is growing well. Get a good kit and don't forget magnesium.

Calcium has always been the biggest drop for me. I don't use Kalk or anything complicated b/c I don't have space for too much equipment. But I use simple Calcium supplements and my SPS grow like mad. I keep my Mag on the high end and does a little heavy on strontium and molybdenum.

 

[mrdobie]

this is why I changed from reef crystal to tropical marine. after 3 or 4 water changes parameters are starting to level out. I've used reef crystal on and off for years and years. just got fed up and had to change for good.

 

[Dan_P]

Always good to check your test kit once in a while with a friend or at a pet store. Just had that happen with a Salifert kit that suddenly stopped working.

BTW. Make sure you test your magnesium, that also affects both PH and dKH. Also, have you been dosing calcium and baking soda?

******
DISCLOSURE... this is something i've realized a while ago, but I may be wrong either COMPLETELY or just in the way I did a Math. I welcome any disagreement.
******

One thing to note too: doing a water change helps, but from true impact, you won't get much of a result from partial changes. If you think about it, to get any chemical level to where you want, you'd have to do a 100% water change. I suck at math, but I'll try this:

Parameters:
Calcium 100 (just for simplicity sake)
Desired Calcium: 200
Gallons 100
Water Change: 10%
New water has 200 Calcium

You do the water change, results:

10% of water has (ie 10 gallons) has 200 calcium
90 gallons has 100
Extra amount of Calcium is 100

You have to divide the newly added calcium by the TOTAL number of gallons of the tank, so:

100 Calcium divided by 100 = 1

You just increased your calcium by 1. Your new calcium level is 101. Not much of an improvement.

These are fake numbers, but it's just for demonstration purposes.

And, here's another thing, even if you do a 10% water change every day for 10 days, you'll still never reach the desired Calcium level because after the first water change, you start replacing new water.

The new calcium level in your example is calculated this way

(90/100) x 100 ppm + (10/100)x200 ppm = 90 ppm + 20 ppm = 110 ppm

 

[Fourevrloud]

this is why I changed from reef crystal to tropical marine. after 3 or 4 water changes parameters are starting to level out. I've used reef crystal on and off for years and years. just got fed up and had to change for good.

I've heard this salt is the best out there right now
I was debating on switching over

 

[sgdcover]

The new calcium level in your example is calculated this way

(90/100) x 100 ppm + (10/100)x200 ppm = 90 ppm + 20 ppm = 110 ppm

Thanks. I'm far from a math genius. So if we use real numbers:

(92/100) x 380ppm= 349.6
(20/100) x 420ppm= 84
349.6ppm + 42ppm = 392ppm

I must have done this wrong. How can a ~20% partial water change increase it by so much? I?m going by my gut here, which could easily be off.

Is the generic formula this?

Where:
G=Tank Gallons
CaO=Current Calcium level in the tank
AC=Water change amount in gals
CaNW=Calcium level of new water
CaNT=Calcium level of tank after water change

G/100 x Ca0 + AC/100 x CaNW = CaNT

Did I get that right?

 

[Dan_P]

Thanks. I'm far from a math genius. So if we use real numbers:

(92/100) x 380ppm= 349.6
(20/100) x 420ppm= 84
349.6ppm + 42ppm = 392ppm

I must have done this wrong. How can a ~20% partial water change increase it by so much? I?m going by my gut here, which could easily be off.

Is the generic formula this?

Where:
G=Tank Gallons
CaO=Current Calcium level in the tank
AC=Water change amount in gals
CaNW=Calcium level of new water
CaNT=Calcium level of tank after water change

G/100 x Ca0 + AC/100 x CaNW = CaNT

Did I get that right?

Looks good!