high magnesium

[Art2249]

I've been reading some posts about using high MG (1500) to combat algae. Does anybody know about this? Does it work and if so how? Any side effects?

 

[saltyfilmfolks]

It doesn’t work.

The consensus is it was an impurity in the magnesium that killed the algaes. Lithium.

What kind of Algae do you have ?

 

[AllSignsPointToFish]

It doesn’t work.

The consensus is it was an impurity in the magnesium that killed the algaes. Lithium.

What kind of Algae do you have ?

Agreed. My magnesium usually runs high, but the only thing that I've found that kills algae is low nutrients.

 

[Hillbillyreefer]

Ive tried high mag a couple of times with no positive results.

 

[Art2249]

It doesn’t work.

The consensus is it was an impurity in the magnesium that killed the algaes. Lithium.

What kind of Algae do you have ?

I have GHA. It's not at the panic stage yet. I do have a gold spot rabbitfish in qt for a couple more weeks. He eats sheet algae like a cow so we'll see. He will be followed by tangs. That might solve my problem. Nitrates are at 4 ppm and phosphate stays below .01 unless I add some. When i raise it to .025 I just get a burst of algae growth until it drops back down. But I'm thinking the extremely low phosphate may be hurting my corals.

 

[AllSignsPointToFish]

I have GHA. It's not at the panic stage yet. I do have a gold spot rabbitfish in qt for a couple more weeks. He eats sheet algae like a cow so we'll see. He will be followed by tangs. That might solve my problem. Nitrates are at 4 ppm and phosphate stays below .01 unless I add some. When i raise it to .025 I just get a burst of algae growth until it drops back down. But I'm thinking the extremely low phosphate may be hurting my corals.

You're probably correct. I keep my phosphate in the 0.02-0.08ppm range and nitrates in the 0.5-1.5ppm range. My tank is primarily LPS with a few SPS and softies.

The GHA algae disappeared completely when nitrates were undetectable, but the corals were not happy. Phosphates at this time were also <0.02ppm. I think if you could drop and control your nitrates around 1ppm, you'd find the GHA slowly disappears.

 

[Art2249]

You're probably correct. I keep my phosphate in the 0.02-0.08ppm range and nitrates in the 0.5-1.5ppm range. My tank is primarily LPS with a few SPS and softies.

The GHA algae disappeared completely when nitrates were undetectable, but the corals were not happy. Phosphates at this time were also <0.02ppm. I think if you could drop and control your nitrates around 1ppm, you'd find the GHA slowly disappears.

Yea it was around 2 ppm until my macro died back in the fuge. It's gonna be tough to drop down that low. I can cut back on feedong and try. Right now i do 5% biweekly water change. i hate to do more because it uses up a lot of salt. Tank holds 160 gallons after the sand and rock was put in. Tank is a little over 8 months old and still settling in. i probably just need to ride it out. I do have some vibrant ordered as a last resort. But it will have to get much worse before I go there. I plan on giving the herbivores a chance first. maybe adding some more CUC. It's tough to get large batches og cuc through qt since my qt tank only holds 20 gallons.( that's a seperate qt from my fish qt)

 

[AllSignsPointToFish]

Yea it was around 2 ppm until my macro died back in the fuge. It's gonna be tough to drop down that low. I can cut back on feedong and try. Right now i do 5% biweekly water change. i hate to do more because it uses up a lot of salt. Tank holds 160 gallons after the sand and rock was put in. Tank is a little over 8 months old and still settling in. i probably just need to ride it out. I do have some vibrant ordered as a last resort. But it will have to get much worse before I go there. I plan on giving the herbivores a chance first. maybe adding some more CUC. It's tough to get large batches og cuc through qt since my qt tank only holds 20 gallons.( that's a seperate qt from my fish qt)

I started carbon dosing almost immediately after the tank was set up. Carbon dosing really knocks down the nitrates...so much so that I think my corals were starving. In fact, I never actually went through the "ugly" phase with GHA and such.

I measure nitrates weekly with a Red Sea test and adjust my dosing pump to keep nitrates around 1ppm, depending on how much I feed in any given week. The nitrates are really pretty easy to control with carbon dosing, but you have to have an oversized skimmer for it to work properly. I do monthly 25-30% water changes as well to keep other ions in check since I also dose Randy's 3-part DIY system.

 

[saltyfilmfolks]

I don’t pay attention to my nutrients at all. They prob run high ,maybe.

I rarely have gha or anything else.
I have a lot of snails and tuxedo urchins. And a toothbrush.

 

[Jason mack]

I must be the exception too the rule ...raising mag worked for me a couple of years ago ..although I needed too be raised above 1700-1800...I used Colombo mag ...but like @saltyfilmfolks said it might have been an additive in that ..

 

[KilianSP]

I only have macroalgae tanks.
In 3 the macroalgaes are nownot doing great after i hocked a auto doser and dosing aquaforest 1,2,3 which also adds Magnesium.
For nitrates i dose a fertilizer which also contains Magnesium, since i need alot of nitrate in a fishless System i added alot.
Now i got 1 tank where everything is fine, because i habe fish in there and don't need to add nitrate fertilizer.
Long Story short, the 3 tanks where the macroalgaes don't do great have Magnesium way over 1500mg/l in the tank which is running fine, it is around 1370

So i am going to do big water changes till my Magnesium comes down to 1400 and then i watch if they do better.
Nutrient and trace element limitation is no way, since i am dosing daily.