Another Reef Chemistry Noob

[Coastie Reefer]

Finally starting to test and document my parameters.

Using IO salt my parameters are as follows:

Ca - 310 (repeated test same results) Salifert
Mg -850 (repeated test same results) Salifert
dKH - 8.7 Hanna check
Salinity - 1.025 refractometer

Ca and Mg seem really low. Tank is 20 gallon with very low bio-load but has about 10 nice SPS frags of different varieties. Most are encrusting nicely.

Thoughts, comments, and suggestions highly appreciated.

 

[Tori]

Finally starting to test and document my parameters.

Using IO salt my parameters are as follows:

Ca - 310 (repeated test same results) Salifert
Mg -850 (repeated test same results) Salifert
dKH - 8.7 Hanna check
Salinity - 1.025 refractometer

Ca and Mg seem really low. Tank is 20 gallon with very low bio-load but has about 10 nice SPS frags of different varieties. Most are encrusting nicely.

Thoughts, comments, and suggestions highly appreciated.

What does your water change schedule look like?

 

[Coastie Reefer]

Change about 5 gallons every 2 weeks. Just did a wc on Sunday... I'm guessing my salt mixes low?

 

[Tori]

I'm no expert and I've never used instant ocean but it doesn't seem like your Ca and Mg should be that low 1.025 salinity to me. Have you tested your salt mix?

 

[Randy Holmes-Farley]

I don't believe the magnesium result is accurate. Don't boost it. Magnesium is plenty high in IO and it depletes very slowly if at all.

Maybe the salinity measurement is off, or you are reading the test kit syringes backwards?

 

[Coastie Reefer]

I don't believe the magnesium result is accurate. Don't boost it. Magnesium is plenty high in IO and it depletes very slowly if at all.

Maybe the salinity measurement is off, or you are reading the test kit syringes backwards?

I don't believe I'm reading it backwards... I'm reading the lower end of the plunger. I'm using the tip that's included so am I reading the result incorrectly? Is it better or easier do the test without the included tip?

 

[Coastie Reefer]

Tested again tonight. Ca read 375 and Mg read 900. Repeated both tests with same exact same results. Feel a little better about the calcium, but still stumped about the mag. I know the tests are good as they're brand new Salifert kits. Sigh...

 

[hawkinsrgk]

I would test your saltwater batch. I use instant ocean as well and the last time I tested a batch it seemed to be higher in alk than calcium or magnesium

How are you mixing a batch of saltwater? Assuming the values you are saying are correct, it almost sounds as if you are using a little salt from a bucket that needs a good shake.

 

[Coastie Reefer]

Just tested my water change water. Ca 350, Mg 900, salinity 1.025. I'll try giving my salt mix a good stir and test a fresh batch. At least I'm getting more comfortable with my testing...

I would test your saltwater batch. I use instant ocean as well and the last time I tested a batch it seemed to be higher in alk than calcium or magnesium

How are you mixing a batch of saltwater? Assuming the values you are saying are correct, it almost sounds as if you are using a little salt from a bucket that needs a good shake.

 

[Coastie Reefer]

Stirred my salt bucket like a mad man... nearly broke the slotted spoon. Don't tell my wife. Exact same results as what's in my water change container. Could I have a bad batch of salt mix?

 

[hawkinsrgk]

I guess it's possible. I did have one bad batch of reef crystals one time. For me the odds have been very low. With that being said I mix a whole bag at a time

 

[Randy Holmes-Farley]

I don't believe I'm reading it backwards... I'm reading the lower end of the plunger. I'm using the tip that's included so am I reading the result incorrectly? Is it better or easier do the test without the included tip?

Quite a few people read it backwards. The easiest way to be sure is to be certain that more liquid dispensed to get to the endpoint means more magnesium. :)

 

[Randy Holmes-Farley]

Stirred my salt bucket like a mad man... nearly broke the slotted spoon. Don't tell my wife. Exact same results as what's in my water change container. Could I have a bad batch of salt mix?

Possible, or a testing error of some kind.

 

[Coastie Reefer]

The bucket has a 04/09 just over the barcode. Is that the mfg date? If so, 1) wow I got an old bucket 2) didn't older buckets have lower Ca and Mg?

 

[Randy Holmes-Farley]

The bucket has a 04/09 just over the barcode. Is that the mfg date? If so, 1) wow I got an old bucket 2) didn't older buckets have lower Ca and Mg?

Not low like those values, especially magneisum. I don't know if that is a date or not. :)

 

[MaiReef]

Have your lfs test to verify?

 

[ksc]

The bucket has a 04/09 just over the barcode. Is that the mfg date? If so, 1) wow I got an old bucket 2) didn't older buckets have lower Ca and Mg?

I just checked a new bucket of IO I got last week. It has the 04/09 number under the bar code. I don't think they put dates on the bucket. You could try contacting IO directly and ask, as there is a sticker with numbers on the cap, which is different on each bucket I have.

 

[Coastie Reefer]

Have your lfs test to verify?

Thought about that this morning too. Probably do that tomorrow...

 

[Coastie Reefer]

Just left the LFS. Only had Api tests, but Ca came in at 300. That corresponds with my earlier Salifert tests.

I'm going to give my salt mix another good shake, stir, and hand mix. Mix a fresh 5 gallon batch of saltwater, then retest. Based on those results I guess I'll be ordering some supplemental elements.

I know some swear by regular IO, but this is making me seriously consider a new salt.

At least my Alk has been stable at 8.7

 

[Randy Holmes-Farley]

Just left the LFS. Only had Api tests, but Ca came in at 300. That corresponds with my earlier Salifert tests.

I'm going to give my salt mix another good shake, stir, and hand mix. Mix a fresh 5 gallon batch of saltwater, then retest. Based on those results I guess I'll be ordering some supplemental elements.

I know some swear by regular IO, but this is making me seriously consider a new salt.

At least my Alk has been stable at 8.7

How do you know you do not have low salinity?