Hey Dr. Holmes-Farley (and others) am I figuring correct?

beaslbob · Oct 14, 2015

I remember Suzy's planted marine tank in advanced aquariumists years ago. In posts/pms she stated she had found that macros thrive with iron but dosing over 1ppm affected the corals.

So I got out my red sea iron kit and it measured 0. The test is calibrated so a transparent blue for 0 and slight red (very slight) for .05ppm. I was transparent blue.

So I get some ferris gluconate, a 12 oz coke bottle and shook it for an hour trying to get all the pill to dissolve. I then poured the water into a glass, dumped out the small amount of crud, and poured the water back into the bottle. I dosed about 1/3 the bottle and still tested 0. So I dosed the rest and still test 0.

So are these calculations anywhere near reality?

density of water 3.79kg/gallon*1.026 (sg) is about 3.88854kg or 3888.54 grams. *60 gallons=233312.4000 grams

the iron tablet has 28 mg of iron or .028 grams.

If I dosed the entire pill would the iron density be .028/233312.4=.00000012 or .12 ppm iron?

I also at first forgot to multiply by the 60 gallons and found out in 1 gallon you get about 7.2ppm.

If the logic is good I can understand Dr. Holmes-Farley's statement that dosing a capful will provide some iron but at such a low does to not affect the corals.

Can you make corrections of if that is correct suggest another form of iron to dose?

TIA to whoever answers

Randy Holmes-Farley · Oct 14, 2015

Iron should read zero in seawater with any kit available (IMO). Natural levels is surface seawater are only about 0.000006 ppm.

So you could dose 10,000 times the natural level and still not reach 0.1 ppm.

A 28 mg tablet in 60 gallons will be about 0.12 ppm. 1/3 of that is about 0.04 ppm. That's plenty, IMO.

beaslbob · Oct 14, 2015

Randy Holmes-Farley said:
Iron should read zero in seawater with any kit available (IMO). Natural levels is surface seawater are only about 0.000006 ppm.

So you could dose 10,000 times the natural level and still not reach 0.1 ppm.

A 28 mg tablet in 60 gallons will be about 0.12 ppm. 1/3 of that is about 0.04 ppm. That's plenty, IMO.

thanks.

been 50 years since I took chemistry. LOL

Randy Holmes-Farley · Oct 14, 2015

You're welcome.

Happy reefing.

JimWelsh · Oct 14, 2015

Beaslbob can math!

beaslbob · Oct 15, 2015

JimWelsh said:
Beaslbob can math!

You didn't see all the mistakes I made before posting.

As I remember from chemistry, things were based on moles. Which I thought were kinds weird animals you don't want in your garden. And that moles were based on the concentration of the particles/ions whatever. I wasn't sure if the ppm was strictly based on mass/weight.

So I really do appreciate Dr. Randy confirming my calculations even if I had to take several stabs to get it in the ball part let alone correct.

Which is worth a lot to me but to others only.

.02