PMDD Liquid Aquarium Fertiliser

[congo]

I would appreciate info from those of you who have tried the PMDD (poor man's dupla drops) recipe from places such as

http://www.thekrib.com/Plants/Fertilizer/pmdd-tim.html

There is obvious success in the US, but am interested in where people got their stuff from in NZ.

Specifically? Where from for k2so4 mgs04 kn03, chelated trace mix? (special brands of trace mix? content? recommendations?) Work well? Kill everything?

Thanks guys

Congo

[Warren]

I make my own.

I get the macro's from a place called Clake Products who is a wholesale chemical supplier. I get the trace from Aquarium Pharmaceutical Aquatic Plant Stimulant. It doesn't quite have the right balance but it's close enough. I get iron chelates and HCl from Clarke Products as well.

I find it works great. With CO2 I get 100-125mm/day growth on Cabomba and 50-80mm a day on most stem plants. Swords throw a complete new leaf every 2 days. Java Fern doubles in size every month and Anubias in 2 months. Apart from the trace elements, my mix is fairly close to the PMDD recepie. I've changed it a little from time to time to suit the type of plants I'm growing. A planted tank gets a bit boring after it's the same for 4-5 years. I now change the type, quantities and layout of the plants every year or so and have to change the mix slightly to suit. The main ingredients to adjust are Mg, K and Fe depending on the quantity of fast growers and iron lovers...

[cees]

agree with warren.

When I still had a planted tank I made my own pmdd. Got most of my supplies from the otaki hydroponics shop. Some of the trace elements where probably scraped of my lab-bench at work.

Had to be careful not to overdose though. After a couple of months I had it figured out and the tank (100L only) was nitrate limited with good growth.

You need to do everything though CO2, light, fertiliizer etc. I also had heating cable in the substrate, very efficient.

Perhaps this winter I'll get a 4 foot tank and start with the plants again :-)

Cees

[congo]

Hi again,

Thanks for the Otaki heads up. Have contacted them and they seem better than nearly everywhere in AKL!

Trouble now is to find a suitable trace element mix. Recommended in US is something like

Fe 6.53%

Mn 1.87%

Mg 1.40%

Zn 0.37%

Cu 0.09%

Mo 0.05%

B 1.18%

Co 0.00%

Otaki have advised that their trace mix contains:

Our A45 TE has the following ratios:

Al 0.00%

B 0.66%

Co 0.00%

Cu 0.28%

Fe 10.45%

Mn 3.52%

Mo 0.08%

Zn 0.20%

Does this sound suitable for PMDD. I see it has lots of iron in which sounds good, but am generally unfamiliar with for example how much zinc is needed and whether having half of someone else's mix is bad etc. Getting there tho and thanks for the help thus far.

[DiverJohn]

Hi Congo,

Would be interested in some of the trace element mix if you ended up getting too much.

Diver John

[congo]

As luck would have it I had to buy lots of chems in bulk to 'save' money. Also got them to make a custom trace mix so spent >$50. =)

So could prob mix you up a powder form of the PMDD and mail to you for say $5? + 45 c postage. Havent tried it on my tank yet so no guarantees. Hope it works!

[freshwest]

I just got some trace element mix from Stokers hydroponics . Thay made it up as to the pmdd recipe . Thay had to make up 2 kgs to get the right % . Im going to keep 1 kg the rest is up for grabs . Cost me $2.50 / 100 grams . I would rather trade fert for plants ( suitable for discus tank). I can also send the Macros that you will need to make up the pmdd recipe . The macros are agricultural grade not lab grade .

[Luke*]

Mine works well, but i find like flourish excel it often leaves a slimey coat on the surface of the tank. This is likely just too much fert that is being consumed or maybe it is one nutrient in excess. My trace element states it has balanced proportions. The slime can easily be removed through siphoning the surface of the water or just doing a water change to break it up and dissolve it, it is a pain though as it cuts down on light levels. The advantages exceed the disadvantages though and is especially economic compared to commerical ferts.

You want 0.1 ppm of iron so you could invest in a kit. Any more or any less the authors of PMDD at thekrib state has equally detrimental effects. Just like any nutrient, it should be just right.

My mix is a combination of macro nutrients N-P-K and micro nutrients (trace elements) but you could have them separate the N, P, and K, as well as the trace elements. Every setup will have different requirements for the nutrients but I don't know how you're supposed to know which are more or less required for certain plants and setups.