Cal/Alk/PH Guidance

[HughJas]

I've noticed recently that my Calcium is pretty high while at the same time my PH is fairly low.

 

Here's my stats so far.

 

SG : 1.024

Ammonia : 0ppm

Trites/Trates : 0ppm

PH : 7.6 ~ 7.8

Alk : 300ppm

Cal : >520ppm (my test kit stops at 520)

 

The tank is 3mos old.

 

Cal has always been high and I never dose anything. That's got me wondering what's putting it there. The lowest I've seen Cal in this tank is 440ppm.

 

The only guys in there to use the CAL are a couple heads of frogspawn and candycane, and some halimeda. Nothing that would require alot of CAL.

 

There's a possibility of a test kit problem but I would expect to see the same results on another tank, but I don't. Just to eliminate it I'll try to pick up another one today.

 

PH has always been low. This tank sits in my office so who knows, it could be all the CO2 in the room that I'm blowin off during the day.

 

So here's my question - are high CAL and low PH tied together? None of the other parameters seem out of whack except for those two.

 

Any insight is appreciated.

 

~CHRIS

[tinyreef]

what kind of source water are you using?

 

i'm thinking it might be well-water of some sort since you're not dosing anything. hard water with CaCl maybe or CaCo3, e.g. terrestrial lime deposits. the Ca+ and Cl- breakdown affecting the high Ca and low pH (more acidic). maybe the CO3 breaks down for more CO2, i dunno.

 

really grasping here tho.

[bobioden]

What salt brand are you using. Some are alot higher in CA than others. Also what test kit are you using to test the CA?

 

Bob

[Jpizzle]

my first guess would be that he uses Oceanic salt.

 

It's a good idea to get a good calcium test (salifert is good).. even better to get 2 to compare.. but it might not be necessary. borrow one from a local reefer or go to a quality LFS

 

at least you know your pH to low.. that could definitely cause problems.

 

it also might be worth while to get a magnesium test. Mag is closely related to how stable your KH and calcium levels are.

[Cesar]

I have the same issue here. I cant bring my CA levels down. Im not even dosing with any.

[techabytes]

So do I, but my PH is a bit better, 8.0-8.1. I think its staying more stable because I do frequent, small water changes. But my CA averages 650, has for a long time. Doesn't harm anything, but I have very few corals right now. I'm seriously considering starting to dose with that two step buffer/CA to put it under control, my alkalinity is on the low side too.

 

And I use Oceanic Salt too, I know its a high CA one. Nothing else is available locally.

[Cesar]

I buy my water pre-mixed so im not sure what is causing the CA spike. It might be the salt they use. Im going to ask next time I go. But then again they are going to say "oh no buy this.This thing will bring it down" just to make a buck.

[Jpizzle]

to all those who are using oceaninc salt in this thread-

 

try mixing oceanic salt with instant ocean. I read about people doing that in order to get optimal levels.

[HughJas]

I use Instant Ocean as my mix. I used Oceanic for a bit but switched back since I saw alot of people saying they had trouble.

 

I took Tiny's response and tested my topoff water. Right now it's tap (my RO/DI should be here in a few days) and it registers about 75 total hardness.

 

CAL is not so much my concern as the PH is. Should I start dosing something to bring it up? I have 3 different PH tests and they all register 7.6 - 7.8 so I know it's definitely a problem.

 

So far none of the inhabitants have shown any signs of stress and some are doing quite well.

 

Thanks for the help so far guys.

 

~CHRIS

[joshceo]

i had a ph problem (like ph of 7) when i started using ro water.. u might want to make sure you have a power head or something pointed at the waters surface or something to promote gas exchange. it helped for me plus i use a small amount of reef buffer in my top off water.

[Brianc_4]

Ok CA can affect pH. But not downward. Calcium is a natural buffer, and if anything should help stabalize your pH and raise your alk and KH. So I do not think your CA level would have anything to do with your dropping pH.

So I would look at why your pH is dropping. Dropping pH is a sign that your buffers are wearing out. The main causes for increased acid are CO2 from respiration, nitric acid from biological filtratation and acids from natural waste. Poor gas exchange may be the cause i would try stronger surface agitation. If you run any artificial bio filtration, i would stop. Of Course regular water changes are the best way to refresh your buffer capacity. Also take a realistic look at your tank excess waste, detritus or an overloaded bio load will all cause an increase in nitric acid and CO2 which may be beyond what your KH can handle.

If after all this you may actually want to start dosing...I know i know you thought your CA was too high and might be the cause. I assure you the high CA is not the cause. But a 2 part alk and CA might actually help balance out the Alkalinity to help raise and maintain the pH. You could also try the a quick fix bicarbonate method to temporarily raise the pH and see if you can raise your dKH at the same tme to maintain it.

I hope this helped , I know i was begining to ramble heh.

[Polareef]

Yep,

 

I've got this one too. I haven't tested my calcium much but when I tried yesterday I stopped the test after the numbers exceeded 450. I have no idea how much higher it would have gone if I had kept adding the drops to the test kit (probably all the way to $12.95 for new kit). I thought maybe it was because I was adding a little Seachem Reef Calcium over the past three weeks however that stuff is only supposed to add 3mg/l of calcium just for maintenance. It made me wonder where all the calcium was from?

 

I don't use a salt mix but use Catalina water and use RO/DI for topoff.

 

I thought that maybe the excess calcium was from an 3.5" layer of agoronite sand or a few large limestone base rocks.

 

My specs are:

SG 1.024

Nitrate 0

Nitrite 0

Alk 300

pH (varies from 8.0 to about 8.6)

CA > 450

 

200gph flow.

 

I have two porites corals that are doing ok. Even with all this calcium I still can't get coraline to grow anywhere but the few liverocks it came in on. I have an algae problem that is slowly going away. Also grow macroalgae. I am going to put a skimmer online here in a few days so I hope that will help things.

[techabytes]

Well I'm beginning to dose, my ph fell to 7.9 today, and my alkalinity is still on the low end of normal. I started with the 2 part CA and alk, just one ml of each. I'm also going to reposition a powerhead to point more at the surface, I didn't realize that would help.

[dzhuo]

are anyone of you guys dripping kalk (lime water)? if not, you can try that. i have a 10G and i drip one drop per 6 seconds. lime water is prepared with 1 tsp of pickling lime per 1 gallone of distill water. this really keeps to the pH and alk high. in fact, it's so effective (pH over 8.6) that i have since stopped dripping. once i have stopped, both pH and alk drop back. i am planning to drip again (this time with half the dosage of pickling lime) because i found this to be the most effective way to maintain my pH and alk.

 

i am using IO salt and when i tested pH, cal and alk in a fresh mix (with distill water), they are all low (cal in the 300 range, for example). i have heard that IO is not designed to mix well with distill water so the buffering capability is effected with mix with distill or RO/DI. my tset so far seems to confirm this.

 

thanks!

[HughJas]

Well this has given me alot to go with.

 

It has bee a while since my last water change so I'll start there. I'll keep going down the line until I find the resolution.

[HughJas]

Another question - my ALK tests 300ppm regularly. Even though the ALK is high could it still be "wearing out" and not being as effective?

 

~CHRIS

[HughJas]

After a water change and a little buffer my PH is now 8.2. I'll be keeping an eye on things to see where it goes from here.

 

Thanks for the help...