Potassium Dosage

[Peyton]

I've been try to find out how much potassium to add since I have no way of testing for it. I'm using flourish potassium. Using this website http://www.leon-huang.com/doser/ I must add 17 ml (!) to reach the desired 10-20 ppm to 20gal (or 75.6 liter). Is this calculation correct? Just seems way too large of a dose. According to the stickies I should also dose an additional 5+ml a second time during the week. At this rate I will deplete my 250ml bottle in no time.

 

[Purrbox]

This is why the dry ferts from GregWatson are so popular. They're much less expensive and last a lot longer. The concentrations on the Flourish products aren't very strong which is why you find yourself dosing so much when you start trying to hit targets instead of just dosing the minimums, which are geared toward much lower light setups.

 

[Peyton]

Wow so it is right then. I guess when my flourish products run out I'll make the switch. Thanks for the quick reply.

 

[Lonewolfblue]

I've been try to find out how much potassium to add since I have no way of testing for it. I'm using flourish potassium. Using this website http://www.leon-huang.com/doser/ I must add 17 ml (!) to reach the desired 10-20 ppm to 20gal (or 75.6 liter). Is this calculation correct? Just seems way too large of a dose. According to the stickies I should also dose an additional 5+ml a second time during the week. At this rate I will deplete my 250ml bottle in no time.

That's 10-20ppm per week, not daily. Divide it by 3 and dose 3 times a week.

I agree, change to Greg Watsons when you are done with the bottle. The 1lb bag will last you quite a while.

 

[7Enigma]

Here's another vote for Greg's ferts. With the way shipping works though, you'd best stock up on anything you might ever need (seems like the first item has about an $8 shipping charge while additional items up the shipping about $0.25).

By far you will go through the potassium sulfate the fastest, but its a good idea to pick up the whole gang of stuff (CSM+B for trace ferts, potassium nitrAte, potassium phosphate, and I got magnesium sulfate just in case I ever have a need for it, though I believe this is the same as epsom salt). Might think about 2lbs of potassium sulfate but the rest will last you a LONG time.

 

[malkore]

Yep. it takes 2/3 of a bottle of Flourish Potassium to give my 75 gallon a 15ppm dose. far from cost effective.

 

[dskidmore]

I personally am wishing I had ordered the Twin Neck bottles with my ferts, for simplified dosing. They're simply impossible to find! (Some guy in Hawaii has 16 oz bottles, but I can't imagine the shipping cost.)

We use these twin necked bottles at work with a cleaning solution, and it's very handy. No mess, measuring is very simple.

 

[JRagg]

I personally am wishing I had ordered the Twin Neck bottles with my ferts, for simplified dosing. They're simply impossible to find! (Some guy in Hawaii has 16 oz bottles, but I can't imagine the shipping cost.)

We use these twin necked bottles at work with a cleaning solution, and it's very handy. No mess, measuring is very simple.

I couldn't agree more on the twin neck bottles. I wish I had bought them, but I don't feel like paying another $8 in shipping to get a few. Sure would make dosing a lot easier.