Alkalinity dropping, magnesium too low

[gooicide]

Hello, my tank has just completed its cycle about a week ago, and since I've been slowly adding a clean-up-crew, I've noticed my alk is dropping, and my magnesium is too low. The alk went from 10.9 to 8.5, and the calcium went up a little bit as expected. I know I don't have corals yet but from what I know higher alkalinity is better for corals. And I worry that it will keep dropping at that rate. Sorry for the ignorance, but do I have to start supplementing anything? Also, will params like this harm anything non-coral tank inhabitants?
Params:
Ammonia, nitrite, nitrate- 0
Calcium- 475
Magnesium- 975

 

[Neil Fox]

Your calcium is a little high but still fine, I usually go a little lower on the Alk but in reality that is right where you want to be. Your magnesium is low but not critical. Try to bring it up to around 1300 over the course of a few days. I would let the Calcium fall to around 400 to 450, anywhere in that range is fine. I wouldn't worry about alk at all, it is really good right there. Much higher can be a problem with low nutrients. I try to keep my alk close to natural sea water, normally around 7. Here is a good link by Randy Farley http://reefkeeping.com/issues/2004-05/rhf/ . There is another one with a chart and explanations of how to keep stuff in the Goldilocks zone but I need to search for it.

 

[gooicide]

Your calcium is a little high but still fine, I usually go a little lower on the Alk but in reality that is right where you want to be. Your magnesium is low but not critical. Try to bring it up to around 1300 over the course of a few days. I would let the Calcium fall to around 400 to 450, anywhere in that range is fine. I wouldn't worry about alk at all, it is really good right there. Much higher can be a problem with low nutrients. I try to keep my alk close to natural sea water, normally around 7. Here is a good link by Randy Farley http://reefkeeping.com/issues/2004-05/rhf/ . There is another one with a chart and explanations of how to keep stuff in the Goldilocks zone but I need to search for it.

How would I go about bringing up my magnesium?

 

[Sabellafella]

Hello, my tank has just completed its cycle about a week ago, and since I've been slowly adding a clean-up-crew, I've noticed my alk is dropping, and my magnesium is too low. The alk went from 10.9 to 8.5, and the calcium went up a little bit as expected. I know I don't have corals yet but from what I know higher alkalinity is better for corals. And I worry that it will keep dropping at that rate. Sorry for the ignorance, but do I have to start supplementing anything? Also, will params like this harm anything non-coral tank inhabitants?
Params:
Ammonia, nitrite, nitrate- 0
Calcium- 475
Magnesium- 975

What maybe going on here, during your cycle time, certain organisms/bacteria will take in alk while they establish themselves. Usually one will see large drops in alk during the cycling process for this reason. Give it some time to level out, then you can start dosing if you need too. First thing youll want to do is make sure your mag is correct and in range before you start dumping stuff in. Now for the mag level, i would test your saltmix today. If it comes up around 1000 ppm youll either have a bad test kit or bad batch of salt. Also check your salinity level(with a trusted instrument), it could be very very low.

 

[Neil Fox]

To raise magnesium it depends on your tank size. You can use the BRS calculator found here: http://www.bulkreefsupply.com/reef-...4A1oo33Ex2L-dh65j0gmqV7_j8qewsSLNEaAlFL8P8HAQ . Don't raise it by more than about 100 points in a day. You need to add a lot to get there. It takes some effort to overdo it without trying. Make sure to wait at least an hour after mixing it up to add it. Epsom Salts are Magnesium Sulfate BTW. If you use that (Epsom Salts) try not to raise by more than 50 points a day otherwise you may have a problem with sulfates. Honestly I don't know what high sulfates would do but I don't think it's the end of the world. Best not to find out though.

 

[gooicide]

What maybe going on here, during your cycle time, certain organisms/bacteria will take in alk while they establish themselves. Usually one will see large drops in alk during the cycling process for this reason. Give it some time to level out, then you can start dosing if you need too. First thing youll want to do is make sure your mag is correct and in range before you start dumping stuff in. Now for the mag level, i would test your saltmix today. If it comes up around 1000 ppm youll either have a bad test kit or bad batch of salt. Also check your salinity level(with a trusted instrument), it could be very very low.

My salinity is 1.025. How do you test a salt mix?

 

[Sabellafella]

My salinity is 1.025. How do you test a salt mix?

Do you do water changes at all?

 

[cromag27 Verified Sponsor]

What salt are you using? to test salt mix just mix up a batch and test the parameters. your Mag is way too low. what test kit are you using?

 

[gooicide]

Do you do water changes at all?

Yes, once a week I do a 15% water change.

 

[Sabellafella]

Yes, once a week I do a 15% water change.

Mix up your saltmix, and before you do your water change test the fresh mixed sw for alk calc and mag. If the test for your mag is normal, its not your test kit, your tank will just be very low then you can dose so on and so forth. If it test low, it can either be the test kit, or the salt mix (witch most likely could be the saltmix).

 

[gooicide]

What salt are you using? to test salt mix just mix up a batch and test the parameters. your Mag is way too low. what test kit are you using?

I'm using reef crystals, and the salifert magnesium profi test kit. I just tested my salt mix and got 1350.

 

[cromag27 Verified Sponsor]

Reef crystals should mix around:

Alk 13
Mg 1440
Ca 490

You can either do water changes to increase your parameters or purchase additives to raise them. before mixing your saltwater it's always a good idea to roll the bucket around to mix up the salt.

 

[Jahalu]

I use reef crystals and find that Mg runs low with them. I buy ESV Mg supplement and follow instructions. Once you get your number up, maintenance is easy. I usually add it weekly to maintain levels. Just keep testing frequently in the beginning until you get a feel for it.

 

[gooicide]

Your calcium is a little high but still fine, I usually go a little lower on the Alk but in reality that is right where you want to be. Your magnesium is low but not critical. Try to bring it up to around 1300 over the course of a few days. I would let the Calcium fall to around 400 to 450, anywhere in that range is fine. I wouldn't worry about alk at all, it is really good right there. Much higher can be a problem with low nutrients. I try to keep my alk close to natural sea water, normally around 7. Here is a good link by Randy Farley http://reefkeeping.com/issues/2004-05/rhf/ . There is another one with a chart and explanations of how to keep stuff in the Goldilocks zone but I need to search for it.

Is there a way to lower calcium without doing large water changes?

 

[Neil Fox]

Just let it drop. It is fine where it's at but you don't want to go higher. It will come down on it's own. 400 to 450 is where you want to be. If you start adding SPS they will use up the calcium and alkalinity very quickly.