Calcium/Alk all wrong - I need help

[gdtpgh]

I am having major problems trying to get my alk and calcium to the proper levels. Apparently I may be inept at using test kits at home because they were measuring close to where I needed to be. I thought I was ok until I saw some issues with some corals so I sent a water sample to Aquarium Water Testing. I got the following results:

On 12/3/07
Ammonia (NH3-4) 0.011 Good
Nitrite (NO2) 0.002 Good
Nitrate (NO3) 0.0 Good
Phosphate (PO4) 0.01 Good
Silica (SiO2-3) 1.1 High
Potassium (K) 307 Low
Calcium (Ca) 297 Low
Boron (B) 3.7 Good
Molybdenum (Mo) 0.2 High
Strontium (Sr) 14.2 High
Magnesium (Mg) 1416 High
Iodine (I¯) 0.00 Low
Copper (Cu++) 0.02 Good
Alkalinity (meq/L) 3.42 Good

As a result I did two 5 gal water changes and slowing started adding ESV Calcium Chloride daily following the instructions. I also added some Kent Iodine. I maintained my daily dripping of kalk (approx 3 gallons per night to match evaporation). I also added some buffer to boost the alk closer to 4. I thought I was doing great per my home test kits (Lamotte) so I tried another sample to AWT and here are the latest results:

1/14/08
Ammonia (NH3-4) Good 0.002
Nitrite (NO2) Good 0.003
Nitrate (NO3) Good 0.5
Phosphate (PO4) Good 0.02
Silica (SiO2-3) Good 0.4
Potassium (K) Low 273
Calcium (Ca) Low 206
Boron (B) Good 5.0
Molybdenum (Mo) High 0.2
Strontium (Sr) Good 10.7
Magnesium (Mg) Good 1101
Iodine (I¯) Good 0.05
Copper (Cu++) Good 0.01
Alkalinity (meq/L) Low 2.43

On the plus side, My iodine level is good. I assume the water changes affected the Strontium level and got it back to a good level. My calcium and alk actually went lower! What am I doing wrong? Where is the calcium going? I've maintained a 55gal tank for years with no issues like this. If you read some older posts I have lost some acros but I got some guidance that it might have been due to a parsite. Montiporas, clams, LPS and soft corals are all fine and growing. Coraline is growing however it's not as pink/purple as my old tank. One other curious issue is that I can't seem to maintain Chaeto in my refugium. The refugium also has some caulerpa but is not growing much either.

Some other info:
Tank size 125 gal with 55 gal sump and 15 gal refugium
1 cup carbon used 2 weeks on and 2 weeks off
Instant Ocean Salt with RO/DI water.
minor fish population but lots of snails
approx 3 inch live sand bed
added Inland aquatics detritivore and fauna kits

Any help would be appreciated

George

 

[mr_X]

hi george. what is your specific gravity? what corals and how many do you have in the tank right now?
have you tested your new salt water? i'm wondering what kind of Ca you are getting from a fresh mix.

i'm thinking your tank is pretty new with noticable ammonia and nitrite.

two 5 gallon waterchanges is not nearly enough IMO. i'd do a 40 or 50 gallon waterchange until i get it straightened out, and not add anything else until you see what you are dealing with in terms of your IO and R.O.D.I. mix :wink:

 

[ChrisRD]

The numbers look fine to me. You mentioned having clams, stony corals and coralline. They will all use significant amounts of Ca/Alk. You're probably just not adding enough to keep up with the demand of the tank. Water changes may not necessarily help this as your salt mix could be low in Ca and/or Alk. You'd have to test the mix to find out...

Unfortunately, there's no easy answer here as every tank is different - it's basically just a trial and error thing and hobby Ca test kits are notoriously inaccurate. You can try taking a sample and then another a few days later and try to determine the Ca/Alk drop. Divide by the number of days between samples and you'll have some idea of the demand per day. You can then use something like this online calculator to determine doseages. That would be a good starting point, and then over time and more testing you'll figure out what doses work to maintain the levels in your tank.

Also, IMO it would make things a bit easier to switch to a balanced two-part additive instead of trying to dose Ca and Alk (buffer) separately. Given that you'll probably need fairly large quantities of additive to match the tank's demand, you may want to look into Randy's DIY two-part as it will be significantly cheaper than an off-the-shelf products. As a future upgrade, you may also want to consider a Ca reactor as well.

HTH

 

[gdtpgh]

The tank was setup in July and the contents of old 55 were moved to this tank. You're the second person who said my ammonia and nitrites are high. What's the issue there? All rock was well seasoned and I had live sand, skimmer produces lots of skimate every 4-5 days, I feed sparingly, flow seems ok with no dead zones. I don't feel like I'm doing anything right with this tank. It sounds like a small ammonia cycle. Could that be? I noticed my Nitrates actually went up from my last test.

Specific Gravity is 35ppm (I think that's equiv to 1.026) I use a refractometer.

Much of this was transferred from my old 55gal.

6 blue green mushrooms
Frogspawn three small heads
small/medium leather
small encrusting montipora and cup montipora
Lots of palythoa 2 dozen or so
colt coral - growing like crazy
small candy cane
tiny blastomussa
two 3-4 inch clams

hawkfish
green chromis
firefish

I can do that water change. I have some made up already.

George

 

[wade1]

MACO is offering a course on chemistry starting this week, in case anyone is interested in learning more about carbonate balance and buffering systems...

http://www.reefs.org/phpBB2/viewtopic.php?p=1406614

http://www.aquaristcourses.org

(Shameless plug!)

I'd agree that your water change volumes are inadequate as MrX stated. Aim for 20-25% of your water volume each change if you know that some chemistry is out of whack. That said - alk/ca are consumed very quickly and will also covary with your pH (see said course above), so time of day can make a difference, especially on a new tank. Both should be added back slowly so as to maintain levels vs spike them up.

 

[ChrisRD]

i'm thinking your tank is pretty new with noticable ammonia and nitrite.

Noticeable in a lab test - not on hobby test kits. Values this low are basically undetectable for most hobbyists (unless you're sending your water to a lab for testing :wink: ) and are basically on par with commonly accepted values for natural seawater.

 

[ChrisRD]

You're the second person who said my ammonia and nitrites are high. What's the issue there?

The issue is people not paying attention to the decimal point... :wink:
These values are NOT high and are not a problem.

 

[gdtpgh]

One correction on the water changes, I typically do 5 gal per week. My initial post said two changes in...I started adding the calcium after the second one but continued to do the 5gal/week.

I will do some larger changes and "try" to get the alk and calcium to where they need to be before adding more kalk.

I was really wondering why people were saying ammonia and nitrites were high when AWT said they were good.....just when you think you understand this stuff you're thrown a curve.

I just don't think there's a tremendous load on calcium in this tank but I guess I'm wrong. I thought I added way too much calcium chloride in the month between AWT tests. My home kit was showing around 500ppm that's what's really bothering me..the huge discrepency between this kit and AWT.

George

George

 

[mr_X]

i was under the impression that any ammonia was bad.

meanwhile, i don't think you have enough calcium demanding corals yet to warrant the low levels, unless of course, you've not done waterchanges for a while, and haven't checked your parameters until you noticed the corals acting funny.
still, check the fresh salt mix.

 

[ChrisRD]

Personally, I would use the calculator I linked above and your most recent test results to figure out what doseages will put you back on track. After that I would check a batch of your new saltwater as X suggested and figure out where you are with that. Large water changes with a salt mix that is low in Ca/Alk will not really be helpful at this point...

For example, if you have say 180 gallons of total water volume and your last test showed Ca at 206 PPM, you need to add 81 teaspoons of the ESV calcium chloride to adjust the level up to 420 PPM (a commonly accepted natural seawater value).

Your Alk is really not that low - natural seawater is commonly given as 2.5 meq/L. 2.5 to 3.5 would be a good target range IMO, and personally I think 4.0 is getting a bit on the high side and not something I would personally shoot for. Again, you can use the calculator linked above to determine how much buffer to add to adjust it to your target level...

 

[gdtpgh]

So there's the crux of the situation....did I lose my acros to parasites (I saw no redbugs) or the low calcium level? I was testing the levels since July using the Lamotte kit and assumed I was around 400. With a relatively light load AND dosing kalk AND adding the calcium chloride thise last month......how could it have dropped 100 points? in addition to having my alk drop from 3.4 to 2.4

It all seems backwards to me, unless I have a large consumer of calcium. If I do, then I agree that my current method of adding kalk and buffer and trying to maintain with kalk won't work and I'll have to look into RHF's two part methodology.

By the way, if my calc load is considered heavy now, I hate to see it when I really start adding corals.

George

 

[ChrisRD]

One other curious issue is that I can't seem to maintain Chaeto in my refugium. The refugium also has some caulerpa but is not growing much either.

Not curious at all given your low phosphate level (a good thing). Elevated phosphate levels can lead to nuisance algaes and inhibit calcification.

 

[gdtpgh]

ChrisRD,

I may have to buy some more ESV....What would be a good regimen of adding that much calcium? What would be the max teaspoons per day?

What will happen to alk as I add that much calcium? Won't that drive alk down?

George

 

[ChrisRD]

If I had to raise my Ca that much I'd probably do it over a few days. It might not be necessary, but I prefer to avoid drastic changes of any kind with water chemistry.

Raising your Ca up to the 400-450 range should not negatively effect your Alk levels - you're basically trying to get back to balanced Ca/Alk levels. Problems can occur when you're pushing one or both of them too high and things get out of balance.

This is why it's generally easier to suppliment with a balanced two-part product - helps minimize the chances of things getting skewed over time (although sometimes slight adjustments may be necessary).

At this point the biggest issue seems to be the discrepancy in results. Hobby test kits - particularly Ca kits are notoriously inaccurate, but I'd be a bit shocked if they were really that far off. I might try other quality test kits to see if I could find ones that matched the lab results more closely. If I had to bet on it, I'd put my money on the lab test, but again, I have no personal experience with that place. You might want to talk to other users of that testing service to see what sort of results they are getting...

 

[wade1]

One thing - if you were using CaCl2, you very well might have forced the alk out of balance. It seems to happen frequently where if you bring ca up, the alk falls and vice versa for a while... I've seen that done due to treating with CaCl2 and adding no additional Mg. Using 2 parts or a calcium reactor is ideal - one part additives, while cheaper are dangerous.

 

[gdtpgh]

I do seem to be in a see-saw battle with alk and calcium. I also noticed my magnesium went down 300 points in a month. So, my best course of action is to:

short term
1. hold off on large water change
2. add the Calcium Chloride (81 teaspoons over several days)
3. while keeping an eye on alkalinity

longer term
1. stop using kalkwasser
2. use two part supplement ala Randy Holmes-Farley
3. consider calc reactor

I appreciate all of the information...this is frustrating.

George

 

[ChrisRD]

The 81 teaspoons was an example. That's assuming the Ca level you got back from the lab is correct and you have 180 gallons of water volume. Figure out what your actual water volume is and use the calculator in the link. You can use this calculator to figure out how much you need to add of a certain product to adjust your Alk and Mag back to target levels as well.

Also, you don't have to stop using kalkwasser - it adds Ca/Alk in balanced quantities, so there's no harm in continuing to use it. The two-part additive can be used in addition to the kalk to supply whatever Ca/Alk is needed that isn't being provided by the kalk.

If you want stop using kalkwasser to simplify things, that's fine as well, you'll just end-up using more two-part additive.

Either way works.

 

[wade1]

My opinion on proceeding would actually be to stop dosing anything unbalanced and do a couple of 20-25% water changes with good quality salt. Keep in mind that IO and most manufacturers use lower than "recommended" alk/ca values - it won't hurt anything to be a bit low, but in balance.

Once you've done a few changes, you can maintain by dosing 2 parts (or a Ca reactor).

If you want to pursue adding straight Ca, I would highly recommend you look into the addition of Mg containing salts in conjunction with it.

FWIW - You probably lost the sps to ionic shock (though it could be any number of things).

 

[gdtpgh]

ChrisRD, I planned on double checking the actual teaspoons but thanks for pointing it out.

Wade, What product would I use to add magnesium? ....just a better salt mix with a higher concentration of Magnesium?

Until I get trough the two part additive article and start making my own, is there a recommended off the shelf two part product?

 

[mr_X]

B-ionic seems to be a decent 2-part product. i think a good salt mix is all you need with that Ca demand.
i kept 10x the corals you have in your tank, in my old 125, and never added anything. just did 30 gallon waterchanges weekly.