Dosing question

keithmeseroll

Community Member
View Badges
Joined
May 27, 2023
Messages
50
Reaction score
22
Location
New Jersey
Rating - 0%
0   0   0
My magnesium was at 1160ppm. I got fluval magnesium. It's a 30 gallon total water system. My question is how much to dose of the product. It's says Add 5 mL per 75 L (20 US Gal.) once a week. Weekly dosage provides 5 mg/L of magnesium. How much would I need to say raise my levels by 10ppm.thanks in advance
 

GoVols

Cobb / Webb - 1989
View Badges
Joined
Nov 29, 2016
Messages
13,078
Reaction score
37,560
Location
In-The-Boro, TN
Rating - 0%
0   0   0
My magnesium was at 1160ppm. I got fluval magnesium. It's a 30 gallon total water system. My question is how much to dose of the product. It's says Add 5 mL per 75 L (20 US Gal.) once a week. Weekly dosage provides 5 mg/L of magnesium. How much would I need to say raise my levels by 10ppm.thanks in advance

To your 30g just dose 4.5ml once a day until you reach your goal. You have to have some displacement, so your not really holding 30 gallons of water.

Do not exceed the daily limit to the product that you use or your ions could bind together making your big 3 (cal, alk and mag) to precipitate out causing lower big 3 parameters. Then it takes about 10 days before you are able to begin dose again.

Just be patient, at times it takes lots of daily doses until your mag truly levels out. Once your mag levels out, it should hold for quite some time, before the need to dose up mag again.
 

GoVols

Cobb / Webb - 1989
View Badges
Joined
Nov 29, 2016
Messages
13,078
Reaction score
37,560
Location
In-The-Boro, TN
Rating - 0%
0   0   0
What are the KH and Calcium? Have you checked Salinity? If your salinity is low your magnesium will be low but so will be your Alkalinity and Calcium.

yep,
A ture salinity level is very important when testing other parameters, before dosing.

Thanks so much for bringing that up.
 

Lavey29

10K Club member
View Badges
Joined
Apr 29, 2021
Messages
11,476
Reaction score
12,163
Location
United States
Rating - 0%
0   0   0
You may want to retest magnesium. If you are doing weekly water changes that suffices to replenish magnesium as it only depletes at 1/10th the rate of alk.
 
OP
OP
K

keithmeseroll

Community Member
View Badges
Joined
May 27, 2023
Messages
50
Reaction score
22
Location
New Jersey
Rating - 0%
0   0   0
You may want to retest magnesium. If you are doing weekly water changes that suffices to replenish magnesium as it only depletes at 1/10th the rate of alk.
I test everyday and record it all down. Mag and calcium drop regularly but alk stays at about a 10. Actually have problems keeping those 2 up. Don't really know why. I use a red sea master test kit and red sea additives for all if needed. Alk stays the same but calcium will drop as well as magnesium. The only time my ALK will raise is if my calcium drops under 400. I use RO water too so not sure what's going on.
 

Lavey29

10K Club member
View Badges
Joined
Apr 29, 2021
Messages
11,476
Reaction score
12,163
Location
United States
Rating - 0%
0   0   0
I test everyday and record it all down. Mag and calcium drop regularly but alk stays at about a 10. Actually have problems keeping those 2 up. Don't really know why. I use a red sea master test kit and red sea additives for all if needed. Alk stays the same but calcium will drop as well as magnesium. The only time my ALK will raise is if my calcium drops under 400. I use RO water too so not sure what's going on.
Depending on the age of the tank and how many corals, alk and cal typically drop proportionally with each other and at some point need to be dosed proportionally. I dose 35ml of alk in the day and 35ml of cal overnight. Magnesium only drops very slightly on a properly balanced tank and may need to be dosed weekly but typically water changes suffice.
 

Lavey29

10K Club member
View Badges
Joined
Apr 29, 2021
Messages
11,476
Reaction score
12,163
Location
United States
Rating - 0%
0   0   0
I found my Mg went down very quick when the coralline took off and grew like crazy. Wouldn't explain the calcium though. I still dose Mg same amount as kh daily with weekly waterchanges.
You have an imbalance in your system. Mag should not be dropping or dosed equal to alk consumption
 

GoVols

Cobb / Webb - 1989
View Badges
Joined
Nov 29, 2016
Messages
13,078
Reaction score
37,560
Location
In-The-Boro, TN
Rating - 0%
0   0   0
I test everyday and record it all down. Mag and calcium drop regularly but alk stays at about a 10. Actually have problems keeping those 2 up. Don't really know why. I use a red sea master test kit and red sea additives for all if needed. Alk stays the same but calcium will drop as well as magnesium. The only time my ALK will raise is if my calcium drops under 400. I use RO water too so not sure what's going on.

You needed the Red Sea Pro kits.
But go with Salifert over their Pro mag kit.

Next time just grab Salifert cal, mag and alk kits.
 

Randy Holmes-Farley

Reef Chemist
View Badges
Joined
Sep 5, 2014
Messages
67,577
Reaction score
64,031
Location
Arlington, Massachusetts, United States
Rating - 0%
0   0   0
Most likely is test error somewhere (likely magnesium, but also possibly salinity). Remote possibility is a low mag salt mix manufacturing error.

Magnesium is not consumed more than about 1/10th of the rate of calcium, so to drop magnesium by more than 100 ppm would have required addition of more than 1,000 ppm of calcium. Consequently, i do not beleive that consumption is causing what you are observing unless you have been adding a lot of calcium for a long time with few water changes.
 
OP
OP
K

keithmeseroll

Community Member
View Badges
Joined
May 27, 2023
Messages
50
Reaction score
22
Location
New Jersey
Rating - 0%
0   0   0
Got a refractometer and test it regularly. At an 0.0126. mag has been fluctuating a bit but remains at a steady decline. Currently at 1320 as of yesterday. Could it be that my tank is too new perhaps and leaching calcium and ALK out of some unseen source? My tank is about 6 months old at this point. Any thoughts would be appreciated
 

Randy Holmes-Farley

Reef Chemist
View Badges
Joined
Sep 5, 2014
Messages
67,577
Reaction score
64,031
Location
Arlington, Massachusetts, United States
Rating - 0%
0   0   0
Got a refractometer and test it regularly. At an 0.0126. mag has been fluctuating a bit but remains at a steady decline. Currently at 1320 as of yesterday. Could it be that my tank is too new perhaps and leaching calcium and ALK out of some unseen source? My tank is about 6 months old at this point. Any thoughts would be appreciated

The most likely problem that is the answer for anyone reporting a magnesium rise or fall over a short period of time is test error or salinity changes. Trying to look for other explanations is generally a wasted effort. I've seen this movie hundreds of times.
 

Going off the ledge: Would you be interested in a drop off aquarium?

  • I currently have a drop off style aquarium

    Votes: 3 1.6%
  • I don’t currently have a drop off style aquarium, but I have in the past.

    Votes: 4 2.1%
  • I haven’t had a drop off style aquarium, but I plan to in the future.

    Votes: 27 14.4%
  • I am interested in a drop off style aquarium, but have no plans to add one in the future.

    Votes: 91 48.7%
  • I am not interested in a drop off style aquarium.

    Votes: 57 30.5%
  • Other.

    Votes: 5 2.7%
Back
Top