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Well, the search page isn't working right now, so I have some questions about aquarium fertilizers. I'm replanting a 30 gal. next week, and I want to prevent the kind of decline in my plant's health that I've seen these past few months. I've come across PMDD in powder form, and it should come with instruction to mix it with water to make liquid fertilizers and dose them accordingly. I want to know if anyone has experience with this stuff, and if they get satisfactory results, or if there are other ferts that are recommended.

Hoping that there must be a word for everything I mean...

illustrate,

What stuff did you get? I have the dry powder of KNO3, KH2PO4, and K2SO4. I used to use Greg Watson’s Plantex plus Iron for the micros, but recently switched to TMG.

Do you know Chuck Gadd’s fertilizer calculator? If not I can provide you with the link. I add my ferts dry (meaning not as a solution but just mixed up in a measuring cup so it dissolves) and don’t create a prepared bottle from which to add a certain amount.

Satisfaction: yes, although it did take me a while to adjust the default values to my specific needs (and I still do).

Hope this helps a little,

Ingo

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Proud Member of the New Jersey Aquatic Gardeners Club

There's no "magic mix' that will solve all problems. How much of this stuff you need to use would be dependent on a number of factors. Also would need to know the "ingredients".

It would be easier to know what you doing before and why the plants failed. Correcting that is the way to go. If your problem was light or Co2 or micro shortage, adding a PMDD solution will not help.

PMDD is old school and was designed for a particular set of circumstances that was common at that time. We've moved on - most people have more efficient lighting and a better grip on Co2. PMDD is not the best choice for a modern well lit Co2 injected tank.

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Some days you're the pigeon and some days you're the statue.

Remember that age and treachery will always triumph over youth and ability.

The tank is a 30 long, with a Fluval Plus power filter. I've got 120 watts of light and switching to a schedule of half lighting for 4 hours in the morning, full strength for 3-4 hours mid-day, and half strength again for 4 hours in the evening (this probably means that the lights won't come on at all until 10am, since I'll want to enjoy them in the evening when I'm actually home). I used to use DIY CO2, but the fluctuations just caused problems in the forms of either green water or contributing to blue-green algae. The other contributor to the algae problem is a lack of macro nutrients, which is the part I'm trying to fix. I'm shying away from plants like hygro. polysperma, moneywort, and a huge piece of driftwood that has become too difficult to clean around, and replanting with more crypts, smaller pieces of driftwood with ferns and anubias, and plants like bacopa and ludwigia and some vals. I realize growth will be slow without CO2, but I'm okay with that, and plan to suplement every other day with Seachem's Flourish Excel (which I already use on my smaller tanks, so it won't be that much more expensive to buy a bigger bottle every couple of months). I also use regular Flourish, and I can get Flourish nitrogen, but I'd rather have an all-in-one macro supplement if possible.

The PMDD contains: magnesium sulfate, potassium nitrate, potassium sulfate, and (Miller Microplex) trace element mix. I guess I realize I'm better off making my own mix to my own porportions... I'm just really not sure what components I need, and I really have no idea where to get the various nitrates and sulfates and whatever else compounds... What are aluminum sulfate, magnesium sulfate, and potassium sulfate all for? What about Potassium nitrate or rock phosphate?

I'd really like to think that all the frustration of using ferts is in the getting started phase and it really becomes much less complicated once you get going...

Hoping that there must be a word for everything I mean...

Hi,
If you get the chance, grab a copy of Diana Walstads' book
"ECOLOGY OF THE PLANTED AQUARIUM." In it you will find
many of the answers to your questions.
The aluminum, magnesium, potassium, are all elements
necessary for good plant growth. The sulfates are an effort
to provide the necessary elements in a form that plants can
easily use.
At one time you could purchase a "package" of the stuff
and then blend it together just for your tank. Try an
internet search, or try the links section of the Aquatic
Gardeners Association. I believe that you would find
what you are looking for there.

Frank


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

If you are using Flourish Excel you want need to much in the way of Macros. Really all you'll need is Nitrogen and Phosphate and a good micro fert like Flourish.

Dose the Excel as normal and the others about 2 times a week in relatively small doses. Using the entire Flourish line wouldn't be too demanding financially as you only need small amounts so the bottles will last a long time.

If you want the chems you can get online fron http://www.gregwatson.com very very cheap , a 1/2 lb will last forever. All you need is Potassium Nitrate and Mono Potassium Phosphate.

If your GH is less the 3dgh use Seachem Equilibrium also.If higher then that you shouldn't need Magnesium.

You were right to give up the DIY co2. Using an Excel method is bettr if you can't spring for pressurised.

Lights fine, get the ferts in order and you'll be able to grow anything.

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Some days you're the pigeon and some days you're the statue.

Remember that age and treachery will always triumph over youth and ability.

I've bought the Flourish Nitrogen supplement to start using, and I have regular Flourish and Excel, so it looks like what I'm missing is the phosphates... Flourish doesn't seem to have a nicely labled bottle of that, so I'm not sure where to go for that. This is the stuff that in powder form you only use a very tiny amount of (a pinch the size of half a grain of rice), right?

Hoping that there must be a word for everything I mean...

IMHO,

If you go the Flourish line, then I believe what you are missing more than Phosphate is Potassium, I don't think there is sufficient Potassium in that product.

Ingo

The Flourish bottle is called Phosphorus, that's the one for Phosphates. Here is the link.

Last edited by LITTLE_FISH at 10-Jan-2006 10:44

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Proud Member of the New Jersey Aquatic Gardeners Club

The Flourish Nitrogen and Phosphorous products are just watered down KNO3 and KH2PO4 as far as I know,(you can check the ingredients) so you should get the same amount of K as if using the powders which will be enough.

Equilibrium has a very high Potassium content as well as Calcium and Magnesium.

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Some days you're the pigeon and some days you're the statue.

Remember that age and treachery will always triumph over youth and ability.

Bensaf,

The Seachem website lists the following:

Guaranteed Analysis
Available Phosphate (P2O5) - 0.3%
Soluble Potassium (K2O) - 0.2%

Now, I know that ppm and % are by far not the same, but wouldn&#8217;t this at least imply that there is less K than P and shouldn&#8217;t the rate of K to P in a tank be ten fold? I think to remember that was discussed and explained to me at some other thread, but my old brain cannot remember these things .

Thanks,

Ingo

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Proud Member of the New Jersey Aquatic Gardeners Club

Yes but don't forget the K in KNO3 !!!

So basically you are dosing 1x N , 1X P therefore 2 X K.

Should be enough there to satisfy the plants. Certainly I don't add any other K other then what's in the KNO3 and KH2PO4. No problems.

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Some days you're the pigeon and some days you're the statue.

Remember that age and treachery will always triumph over youth and ability.