rs18alpha

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Now I'm confused. These two sites have some differences in the amounts of ferts to mix.
For instance, Rotala say to (mix 40.05 grams) of mgso4 in 250 mil water and dose 15ml to get 1.57ppm of mg per dose. That's 4.71 ppm per week.

Aquarium calculators says to (mix30 grams) of mgso4 in 250mil and dose 19mil to get 1.498ppm per dose and a total of 4.495ppm per week.

So which one is right??

Also, rotala doesn't give the mg from the trace. Aquarium calculators does.

Rotala says to (mix 4.95 grams) of kh2po4 in 250 mil and dose 15mil to get 1.37ppm per dose. 4.11per week

Aquarium calculators says to (mix 15 grams) of kh2po4 in 250mil and dose 15 mil to get 1.368 ppm per dose. 4.104per week.
This is a big difference in the amount to mix here.
Which is right??

Rotala doesn't have K2SO4 either. If I need to bump up the K

Next question:
What are my target levels per dose if I'm dosing 3 times a week
N, P, K, Mg, Fe
 

Phishless

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I went to Aquarium Calculators site, seen several things wrong, I suggest leaving it alone.
Compared Zorfox & Rotala calculators and they are spot on.

Now I'm confused. These two sites have some differences in the amounts of ferts to mix.
For instance, Rotala say to (mix 40.05 grams) of mgso4 in 250 mil water and dose 15ml to get 1.57ppm of mg per dose. That's 4.71 ppm per week.
EI target 5ppm 2x week, 250ml w/127g MgSO4*7H2O, each 15ml dosed is 5ppm Mg.

Aquarium calculators says to (mix30 grams) of mgso4 in 250mil and dose 19mil to get 1.498ppm per dose and a total of 4.495ppm per week.
Not sure what is going on @ this site???

So which one is right??

Also, rotala doesn't give the mg from the trace. Aquarium calculators does.
1ppm of Mg from traces maybe, who cares we are estimating.

Rotala says to (mix 4.95 grams) of kh2po4 in 250 mil and dose 15mil to get 1.37ppm per dose. 4.11per week
EI target 1.3ppm 3x week, 250ml w/4.7g KH2PO4, each 15ml dosed is 1.3ppm PO4.

Aquarium calculators says to (mix 15 grams) of kh2po4 in 250mil and dose 15 mil to get 1.368 ppm per dose. 4.104per week.
This is a big difference in the amount to mix here.
Which is right?? This mix would deliver 4.15ppm PO4 per dose.

Rotala doesn't have K2SO4 either. If I need to bump up the K K2SO4 can be selected on Rotala calculator.

Next question:
What are my target levels per dose if I'm dosing 3 times a week
N = 7.5ppm, P = 1.3ppm, K = 7.5ppm, Mg = 3.3ppm, Fe = .2ppm or older was .5ppm
 

rs18alpha

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Feb 3, 2017
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Thanks for the info, I did see the k2so4 on rotala, I don't know how I missed it, my bad.
I read an article on theplantedtank.co.uk that Tom Barr said to read and that site says to add per dose- N 8.1ppm, P 2ppm, K from N&P 5.93ppm, Fe 0.044ppm.
The Fe seems low on this. I was dosing .9ppm per week Fe The other numbers are close
Tom says to start off with high levels, should I bump up the numbers a little bit that you've listed above?

The only thing I don't get is why we need to mix so much MgSO4?

I really appreciate the help, thanks for taking time to help me.
 

Phishless

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The only thing I don't get is why we need to mix so much MgSO4?

You are targeting the Mg.
MgSO4*7H2O has much other crap in it.
With a molecular weight of 246.47 of which Mg only makes up 24.3050 of it. Roughly just under 10%.
Being heptahydrate adds a lot of water on it's own.

Try rotala and zorfox calculators to familiarize yourself with the possibilities.
 

rs18alpha

Subscriber
Feb 3, 2017
240
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Pennsylvania
I went to Aquarium Calculators site, seen several things wrong, I suggest leaving it alone.
Compared Zorfox & Rotala calculators and they are spot on.
I went to Aquarium Calculators site, seen several things wrong, I suggest leaving it alone.
Compared Zorfox & Rotala calculators and they are spot on.
Are the dosing numbers you gave me for a heavy plant load? My tank has a 50 to 60% plant mass. That's a combination of rooted and plants tied to rocks and drift wood.
 

Phishless

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Standard EI, cut it in half if you feel the need, just dose 7.5ml or make a different solution to still dose 15ml.

Just dose 4 days instead of 6.

Many ways to handle this.