bizzare parameters at week 4

[slojmn]

Hi all,

I test my water every week before a water change to get a sense of where things are...this weeks numbers are mighty strange. I re-test whenever numbers seem off. Here is a synopsis of params over last 4 weeks.

date Calcium Mag alk
7/7 410 ppm 1245 x (could not find test kit)
7/16 405 1230 7.3
7/24 500+ 1275 7.0
7/29 260 1440 7.2

Sorry for the numbers smooshed together...I tried to make a nice table but I can't make it work.

All test kits are relatively new...within last 6 months. I am waiting for my Hannah colormeter to test PO4. The tank, 55-60 net gallons sump and tank, is 6 weeks old. All fish (6) look great, one crocea clam looking awesome, Rose anemone (large and with me for 4 years) sulking and moving around but that is to be expected. I have about 12 little sps frags that I put in a few weeks ago...all encrusting, especially one that is growing really well, all coloring up really well, all have polyp extension and look healthy. I knew it was a risk to put the sps frags in so early in the new system but gave it a shot. My zeo regiment is 1/2ltr zeolite, .1ml Start2 1/2 in AM 1/2 in PM, 2 drops bak/food 2x's wk since last week. So the numbers that seem really odd are the high calcium last week to really low this week...though alk staying consistant ( I re-tested these items to be really sure), also high mag reading this week. I have no calcium reactor as of yet, it was suppose to arrive yesterday. I have not put in any supplements at all. I have a slight dusting of brownish film on the glass maybe twice a week...spotty mostly, some purple coralline growth on rocks here and there...but not much to speak of at this point. A little macro algae growth here and there but dying out rapidly. Water change of 15-20% weekly. Water change on tap for later today, zeolites changed out later today as well for the first time.

Any thoughts? I guess I need to go track down a calcium booster if Ca. numbers continue to be so low after a water change. I think the low Ca. with a consistant Alk reading seems odd. Thanks in advance for any of your wisdom and advice

[GTR]

The 260 ca is what I'd expect if the tank sat without additions for several months and I think water changes could at least maintain that low level. I'd really question that result with the kh staying about the same. I don't see any way the ca could go down that far in that amount of time.

SteveU

[slojmn]

I totally agree with you...quite bizarre. These are all Salifert test kits so I feel confident with the readings in the sense of a good test kit brand. The alk test kit is the oldest of the bunch, but not that old. I plan on re-testing later today after a water change and see what I get. I thought the 500+ Calcium reading last week was odd, I tested twice, as I did this week. The calcium test kit was purchased about 4 months ago. Just plain weird all the way around.

[Aged Salt]

Alicia, plz. check your make-up mixture for Ca level. Unfortunately, batch to batch can vary especially if you are making up replacement salt from a 200g bucket as it may not be thoroughly mixed, or if a new bucket of your salt is "bad". Your coral frags will take up some Ca but not to this extent, but coralline algae formation is a Ca consumer. Your bacterial density is also now well seeded & thriving at full capacity as well. If this is a true reading, then corrective action will be necessary for your coral's health as low Ca levels will induce TN. If you use CaCl, watch your ALK[decrease] & salinity[increase]. Bob

[slojmn]

I just had to add a couple of cups of salt to my make up water to bring it up to 1.024...I let it mix for a half hour or so then went to test the Calcium level of the make up water. It must have been to soon as I added the 1st and second reagents from the Salifert kit and the color went right to blue instead of pink. I tried twice and never got to the third reagent as the color went to blue instead of pink after the 2nd reagent was added. I wondered if this happened this morning as well and I just did not notice so I re-tested the tank water a third time, it went to the pink color after reagent 2 and the Calcium tested out at 350ppm compared to 260 ppm this morning. Very strange. I wonder if my test kit is a problem. I hate to go spend another $20 for a new kit as this one is only 4 months old and used about 8 times. I am going to let the make up water sit and mix overnight. I plan on testing the make up water in the morning, re-test the tank prior to the water change, then test after the water change and see what I get. I'll post my findings here. All corals continue to look happy and healthy.

[slojmn]

Okay, I tested make up water this morning. Calcium tested out at 400 ppm with the Salfert test kit. I then re-tested my tank water prior to my water change, tested at 420 ppm. So we went form 260 ppm (tested twice to make sure reading was correct) yesterday morning to 350 ppm yesterday afternoon to 420 ppm this morning. I think I will post to Habib over in the Salifert forum just to get his opinion on this test kit...it happens to have all mismarked bottles but since I know what I am doing and which bottle goes in what order I did not really care...I do think there is a problem somewhere though. I am off to re-test mag and alk as well before my water change just to compare those numbers to yesterday.

Edit update, It seems there may be some problems with my instructions and how to use the new kit...old instructions with new kit. I am waiting to hear from Habib over in his forum but I did a little investigating and I see there is a new kit with a new way to do the test. I appear to have a new kit and it came without instructions so i had to download instructions off the web. These appear to be instructions for the older kits. I will update this when I hear from Habib.