So.... wet's site had a number of different calculators, and I am just going to assume that (eventually) we'll want to recreate them all. We should probably figure out how we are going to structure the site and our files.... this would also be helpful while I am coding up the navigation.

So far we have:

*Nutrient Calculator
*Glossary
*Contact Form

What else is there and how do we want to structure the domain(s)?

Button that prints calculated results.

Post created so we can all get together and discuss how we should go about this.

Your ideas and comments please.

Thanks :)

i18n language selection

Multilingual feature

select multiple ferts e,g, kno3 k2so4 and view the results together in a list

The calculator is currently giving an error for dGH values with MgSO4*7H2O.

If I target 5ppm Mg, the calculator reports dGH as 0.28. Once I've remembered how the degrees of hardness is calculated in this calculator I'll be happy to make the proper pull request.

But to check the maths, Mg is 4.12 times lighter then CaCO3 (molar mass). 5ppm Mg X 4.12 = 20.6ppm CaCO3 equivalent, or 1.154 dGH.

edit: It appears that this error is also present in other nutrients that have CaCO3 equivalents. With CaCl2*2H2O a dose result of 15ppm Ca gives dGH 0.84. Ca is 2.5 times lighter then CaCO3, so 15ppm Ca x 2.5 = 37.5ppm CaCO3, or 2.1 dGH.

If the maths seems funny, think of it this way. If we add 20 grams of CaCO3 to 400 liters of water, we have a net concentration of 50ppm. This is (amount added in grams * 1000) / liters.

The molar mass of CaCO3 is 100.0869, lets round it off to 100 to make the maths easy.
The molar mass of Ca is 40.078, lets round it off to 40.
The molar mass of CO3 is 60.0089, lets round it off to 60.

So we can see that Ca is 40% (by weight) of CaCO3, with CO3 being the remaining 60% of weight.

Lets check some maths. Ca is 2.5 times lighter then CaCO3, so 40 (the molar mass of Ca) x 2.5 = 100 (the molar mass of CaCO3). Check.
So 50ppm of net concentration CaCO3 is 50 / 2.5 = 20ppm Ca. Or, 20ppm Ca * 2.5 = 50ppm CaCO3 equivalent.

Differing international tsp sizes changes fert output

So there is a difference in size between US teaspoons and British teaspoons. The difference is quite dramatic:
1.0 UK tsp = 1.2 US tsp

That's a 20% increase, or a 17% decrease.
http://www.traditionaloven.com/culin...on-tsp-us.html

And there are different sizes of teaspoons internationally, which further compounds the problem of accurate volume.

So which teaspoon was used for the fertilizer weights?

Perhaps adding additional options for various international teaspoons would provide better accuracy.

Adding specifics for Chelator types is a wise idea. there's a decent pH/% chart somewheres..........I have it posted somewhere.

I will post the chart as soon as find it :D

And if I select premix it starts with ada blighty k but to select that one to use I need to select another one then reselect the ada blighty k.

It's probably worth adding some error checking based on the solubility of the nutrients, and providing the user with an error dialog.

Reminder for myself

KCl nutrient output. The ppm of K is correct but the ppm of Cl is not. This is directly the result of the original percentage value of the program. K and Cl should be near the same ppm, K slightly more; e.g. K=12.9ppm, Cl=11.7ppm (not 4.5ppm as the output).

This thread is reserved for discussion between developers regarding code hand-offs etc.

Any bugs, new features, or calculation errors should be put into individual tickets.

http://rotalabutterfly.com/forum/showthread.php/13-Hydrated-VS-Anhydrous-fertz

Some fertz are available in hydrated and non-hydrated forms.

E.g.
calcium nitrate - Ca(NO3)2; Ca(NO3)2_4H2O
magnesium nitrate - Mg(NO3)2; Mg(NO3)_6H2O
magnesium sulfate - MgSO4; MgSO4*7H2O

RB and YANC only list the hydrated forms. With the exception of CaSO4 which includes the hemihydrate and dihydrate forms.

Perhaps include an option to select between these forms.
Perhaps include a note that the anhydrous forms can absorb water from the air which may change the weight and chemical amount.
Perhaps include pictures of each form to show which is which to help users determine this.

50L
DIY
DTPA Fe 7%
Solution
500ml
5ml
result of my dose
adding 25g
Gimme -->

Your addition of 25.0 g DTPA Fe (7%) to your 50.0 L aquarium adds
Element ppm/degree
Fe 35.00

Whereas i'd expected to see "Your addition of 5ml adds .."

Making this an issue so I don't forget to do this. Also we should talk about its implementation.

Fabrizio - any preferences (from a back end standpoint) on how we handle this?

Jason - what was the library you suggested?

Updating suggested dosing levels
"Dose these levels 2-4 times a week for EI. Classic EI depends on good CO2, good circulation, and regular water changes. Light past moderation is not so important."

This dosing suggestion should include caveats about non-CO2 aquariums:

"If the aquarium does not have added CO2, please use the EI Low Light/Weekly calculations."

Please be as specific as possible when reporting Calculations errors. It is most helpful for us if you list the following:

• The compound or premixed product that you tested
• All other form fields that you had filled in

Thank you :)

you cannot add a ppm target, at 0.1 0.5 ...

Making this an issue so I don't forget to create this.

For now I'll just provide you with a plain html page and some sample markup... what url do you want this do eventually be located at and where should the file live? top level? or within its own directory?