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swilcoxen
02/10/2008, 12:30 PM
I've had a 29 gallon reef up for almost a year now. Up until just recently I've been using de-chlorinated tap water (gasp), but finally purchased an RO unit a few weeks back to combat unusually high Phosphates in my tap water. Upon making the switch to RO water, I noticed that after a water change my Calcium levels were down in the 275 - 300 range. This seemed odd to me since I usually found post-water change levels in the 350 range. I had never thought much about this, just figured my salt mix was a little low on Calcium. I use SeaChem Reef Advantage Calcium to supplement, so I would just dose some calcium over the next day or two following a water change to get me back to my target of 425 ppm. The tank doesn't consume much throughout the week, so this was not too much of a chore.

This weekend, after mixing up 10 gallons of saltwater I decided to check Calcium in the freshly mixed water. I was shocked to find it only contained 250 ppm. I checked the test kit (SeaChem) using the reference sample and it checked out ok.

I use Instant Ocean salt mix and subsequently used Reef Advantage Calcium to get it back to my target. Ideally, when I change water this afternoon I won't need to adjust the tank much as I'll be adding water with the right amount of Calcium to tank water having the right amount of Calcium.

I never tested freshly mixed water before (and will be religiously from now on), so I can't say that Instant Ocean wasn't mixing up properly for me before. I always test my tank after a water change and as I mentioned, the difference in post-water change calcium levels pre- and post-RO unit purchase is astounding. My immediate question is this.

Could my tap water contain substantial amounts of Calcium that my R unit is removing? Obviously, the RO unit would remove dissolved Calcium, but it seems extreme to me that RO water plus Instant Ocean only gives me 250 ppm. Could I have a bad bucket of Instant Ocean? Should I consider switching salt mixes? I had talked to someone about that when I first got started because I wanted to make sure my critters were getting "only the best" and was advised to not change anything if my tank was happy.

As a follow-on. I'll be receiving a new 65 gallon tank next weekend and I'm beginning to think that using Reef Advantage Calcium is going to become unworkable at that point. Especially, if freshly mixed water is going to constantly come in at extremely low levels. I've read the articles on 2-part versus Kalkwasser versus Calcium Reactors. I'd be curious to hear some of your thoughts. I have a CO2 system on a freshwater planted tank. That tank will probably be sold in the coming months, so I already have the CO2 tank/regulator for a reactor if I choose to go that route.

Michael
02/10/2008, 12:36 PM
i use tropic marin pro reef salt, it is guranteed nitrate and phosphate free plus it will buff up your ph and calcium levels to the correct amount for sea water, im not knocking your present salt but i can assure you that if you use tropic marin your calcium problem will be no more

Billybeau1
02/10/2008, 12:39 PM
Well the first problem I see is your test kit.

From my testing, the Seachem calcium test kit consistently tests about 70 ppm lower than other kits. Even though the reference solution matched the kit.

I think your calcium is closer to 320-340 or so which would be consistent with what IO produces.

I'd get another calcium kit and check again. You may be surprised at the results.

Even the inexpensive API kits sold at local stores does a pretty good job IMO.

swilcoxen
02/10/2008, 12:42 PM
<a href=showthread.php?s=&postid=11811750#post11811750 target=_blank>Originally posted</a> by mikeydj
i use tropic marin pro reef salt, it is guranteed nitrate and phosphate free plus it will buff up your ph and calcium levels to the correct amount for sea water, im not knocking your present salt but i can assure you that if you use tropic marin your calcium problem will be no more

Fair enough! If I were to ever switch salts, is there any concerns about the change shocking my corals/fish? Theoretically, the chemical compositions should all be similar but I think we all know that they are not.

swilcoxen
02/10/2008, 12:43 PM
<a href=showthread.php?s=&postid=11811775#post11811775 target=_blank>Originally posted</a> by Billybeau1
Well the first problem I see is your test kit.

From my testing, the Seachem calcium test kit consistently tests about 70 ppm lower than other kits. Even though the reference solution matched the kit.

I think your calcium is closer to 320-340 or so which would be consistent with what IO produces.

I'd get another calcium kit and check again. You may be surprised at the results.

Even the inexpensive API kits sold at local stores does a pretty good job IMO.

Thanks for the reply. If that is in fact the case, I could potentially be running my tank at 500 ppm! I haven't had any precipitation problems to date, but is this level dangerous in any way?

Billybeau1
02/10/2008, 12:43 PM
<a href=showthread.php?s=&postid=11811750#post11811750 target=_blank>Originally posted</a> by mikeydj
i use tropic marin pro reef salt, it is guranteed nitrate and phosphate free plus it will buff up your ph and calcium levels to the correct amount for sea water, im not knocking your present salt but i can assure you that if you use tropic marin your calcium problem will be no more

Most if mot all commercial salt mixes advertise nitrate and phosphate free.

I'm glad TM Pro works for you but it won't necessarily work for everyone.

There are plenty of salt mixes out there with higher calcium levels.

Everyones calcium consumption is different and requires different strategies. :)

Mavrk
02/10/2008, 12:44 PM
<a href=showthread.php?s=&postid=11811775#post11811775 target=_blank>Originally posted</a> by Billybeau1
Well the first problem I see is your test kit.

From my testing, the Seachem calcium test kit consistently tests about 70 ppm lower than other kits. Even though the reference solution matched the kit.

I think your calcium is closer to 320-340 or so which would be consistent with what IO produces.

I'd get another calcium kit and check again. You may be surprised at the results.

Even the inexpensive API kits sold at local stores does a pretty good job IMO.

I agree with one addition... If you are not mixing your salt up to 35ppt (1.026SG), then your numbers will be lower. What is your salinity?

Billybeau1
02/10/2008, 12:45 PM
<a href=showthread.php?s=&postid=11811813#post11811813 target=_blank>Originally posted</a> by swilcoxen
Thanks for the reply. If that is in fact the case, I could potentially be running my tank at 500 ppm! I haven't had any precipitation problems to date, but is this level dangerous in any way?

No, if everything else is in balance, you will not likely experience any problems with a calcium level of 500 ppm. Just waisting supplement I suspect. :)

Michael
02/10/2008, 12:48 PM
changing salts with 10% weekly water changes will not affect your water quality, it will slowly improve the chemistry so that the calcium is more stable, hey but this is my opinion, after reading your question again i would say that your calcium reading is low but not dangeriously low, keep testing it and try salifert calcium test kits, i use it and it is great, you will get there, honestly tropic marin does work wonders

Mavrk
02/10/2008, 12:55 PM
Reef Crystals is basically IO with more calcium (and other parameters). If you order it online it is only a 2 or 3 dollars more than IO. If you get it at the LFS it can be 2 or 3x more expensive Seriously, one place near me sells a bucket for $112, but most sell it for around $80. Online it is more like 32 to 40 (DrsF&S have it for 32 right now).

swilcoxen
02/10/2008, 01:00 PM
<a href=showthread.php?s=&postid=11811820#post11811820 target=_blank>Originally posted</a> by Mavrk
I agree with one addition... If you are not mixing your salt up to 35ppt (1.026SG), then your numbers will be lower. What is your salinity?

I'm actually in the 1.024 range.

Billybeau1
02/10/2008, 01:05 PM
Then it all makes sense to me as mixing IO at 1.024 will produce a lower calcium and magnesium level then if you mixed to 1.026

I would get a new test kit. :)

Michael
02/10/2008, 01:16 PM
i agree with billybeau1 get the sg up to 1.026 reef animals prefer higher salt, fish only are ok at 1.024, and i still say get a new test kit

monty
02/10/2008, 01:48 PM
i didnt read all the replies, so im not sure if anyone touched on this.
Depending on your tap water, in some instances tap water contains calcium - so in the past, you were adding it from the tap water in addition to what was in your salt.

when you switched to RO, this was filterred out of the tap water (thats what the RO does, removes just about EVERYTHING from tapwater).

Do a comparison test with a few gallons of your new method as compared to your old method, this should show you a difference in calcium levels......now, im not sure if that would cause the total decrease, but it certainly contributes towards it.

Tropic Marin is definately a great salt mix to switch to. If i remember correctly, when mixed properly its calcium level is around 450. I plan on switching back to that over the next few weeks. I currently use IO, and bring the level up to about 450 (from about 350) while mixing it before it goes in the tank.

tbar
02/10/2008, 08:47 PM
I heard today at a LFS lecture that when IO was first developed they figured most floks were using tap water then. They left the calicum level low so the calcuim in the tap water would make it about right. That would explain the reason for Reef Crystals as someone said before that it's the same thing just higher calcium

rbursek
02/10/2008, 09:13 PM
First go to the Chem Forum and check out the salt mixes thread, yes BB1, that is what Jesse told me at AM when he called on my salt sample results, SC Ca kits check out about 50ppm lower, and you did expose my PM about what happened there!!!!!!!!!!!! Or what they think did!!!!!!!!!! Bad things about a computer, once sent can not to the company mail room and retrieve it!!!! Been there done it!!!!!
Bob

Randy Holmes-Farley
02/11/2008, 06:51 AM
I heard today at a LFS lecture that when IO was first developed they figured most floks were using tap water then. They left the calicum level low so the calcuim in the tap water would make it about right. That would explain the reason for Reef Crystals as someone said before that it's the same thing just higher calcium

That may be true, but perhaps equally important is that it was developed for fish tanks where folks usually didn't really care too much what the calcium level was. No one had reef aquaria when it was developed. The calcium level varies too much in tap water to make any accounting for it useful. It is only 5 ppm in my tap water.