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How to make DIY root fertilizer tablets with clay

56K views 60 replies 29 participants last post by  irresistible 
#1 ·
I found some great articles along the search for diy fertilizers such as this one and that one. But didn't find one entirely to suit my needs. One main thing I kept hearing is you can't add phosphates with iron. They will precipitate, etc. Some of the well known brands such as Flourish Tabs don't have Nitrates and Phosphates added. So I was spending roughly $49 - $1.00 a tablet and they are incomplete as far as nutrients.

Looking around, I found Osmocote and Jobe sticks are great alternatives. They both work great, but aren't customizable. What they give you in the fertilizer is what you get. So if I wanted less phosphates and more potassium, I'm out of luck. So I decided to try the clay route which is a bonus of extra minerals such as a boat load of iron.

Now this gets messy, like incredibly messy if you are doing it right. But it is fun as well if you pretend you are a kid making mud pies.

I sat down and started thinking about what I wanted to include and came up with a list of ingredients based on the two linked articles, guessing, preference and adjusted as I went along on observing the growth. Now mind you, you'll want to experiment around, find out your own blend. Don't be afraid to add or subtract.

This is my personal recipe:

1 cup micros
I start out with a hunk of clay about the size of a 3" square block and add as needed. (Amaco brand is the one I use. Whatever brand, it must be natural clay, not polymeyer)
4 tablespoons KN03
3 tablespoons MgsO4
3 teaspoons K2SO4
2 tablespoons of KH2PO4
1 tablespoon CASO4
Water to help mix

Optional:
Rolling pin or pasta making machine (or patience if you do this by hand)
Wax paper or other surface to roll out and store the tablets as they dry
Butter knife

Supplies gathered:


Cutting up to manageable chunks:


Rolling out sheets of clay:


Adding in fertilizers (I do this for each fertilizer, I don't combine them in the end just because it's much easier for me to work with):




You start to fold it up to blend it in a piece of clay:


Some will fall out:


This is where it gets a little messy. You dip your fingers or pour a little bit of water on some clay and start working it into the piece, adding more clay as necessary until it is all blended and the clay isn't so wet it is sticking to your fingers. You want it pliable again. It will be crunchy textured if you do it in this manner:




If you did it right, you'll end up with this:


Roll out into long tubes, to what ever diameter you want them. I think if you make them much larger than 1/2 you'll not like them as they aren't very handy or easy to push into the substrate. I like to make them around the same size as an ordinary commercial root tab, maybe twice that size if I'm lazy.

Cut at intervals that you desire, I was about 1/4" but I wasn't scientific, just eyeballed it.


You can roll them into balls and I used to do so. Then I found out this is a lot of work and leaving them flat makes them easier to put into the substrate (especially with tweezers). They don't have to be pretty, but functional.

Sit them aside and let dry (away from kids, pets and adults that may want to eat them.) They will turn a lighter color as they dry. I like to flip them over the next day. Takes anywhere from 1 day to a week to fully dry. If you live in a dry climate, they will dry faster. Here, it takes around 3 days. You want to have them throughly dry before putting them in baggies as clay will mold if moist. In fact you can see this in stored clay often times, it's harmless unless you are allergic, though. Stores indefinitely in a cool dry place.

Depending on the size of the cuts, I'll get around 300 - 400 pieces with one batch. You will have more or less depending on how much you make, how big you make them. And the amount of fertilizers in each will vary slightly depending on the same factors and how well you mixed them. They'll last you for a super long time, you can give away some to friends or fellow hobbyist, sell some, etc. And it cost next to nothing for each tablet.

Tips I found along the way:

1. If you have hangnails, a paper cut on your hand or any other open aware, be forewarned. The nitrates (and some of the other chemicals) will burn like crazy. I panicked the first time thought I was getting a chemical burn. Turns out I had a paper cut, lol. Best to wait, tough it out or wear gloves. I don't like the use gloves as it doesn't let you feel the clay texture.

2. You can emulsify the clay in a bit of water and then add in the fertilizers. You'll have to add in clay as well until it is no longer liquid and you can once again mold it. This is a little more tricky as you start out with cake batter consistency and have to get back to a clay that is able to be molded into tablets.

3. Another method I've done is roll out the clay, let it harden, smash it up, add the ferts and slowly add in water until it is back to pliable clay texture.

4. It makes a mess. Have a towel handy, and you will want to be near a faucet (or a bowl of water) to rinse you hands off as you go. Also, clay can stain, so don't wear your Sunday best or use a good towel.
 
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#36 ·
Has anyone tried DIY clay root tabs with osmocote instead of powdered ferts?

I can find threads like this, where people do clay balls with powdered ferts. And I can find threads where people have done gelcaps with osmocote. But I don't see much on using osmocote in clay balls. I can't think of a reason why it wouldn't work but I'd love to hear from someone who has actually done it.
 
#38 ·
I made some of these last weekend and ended up with a ton of them. I'm also doing a little experimenting and in about half of them I put Kelp meal in instead of the dry ferts to see how that works. I asked about using kelp meal quite awhile back and never got a definitive answer and upon searching the web I didn't find much about anyone trying this except for a thread from 2007 on APC and never really found out any results. So I guess my tank will be the guinea pig. I put them in last week and haven't seen any negative effects yet.
 
#43 ·
CaSO4 is Plaster of Paris and MgSO4 is Epsom salt. In this case wikipedia is right.
 
#44 ·
http://aquariumfertilizer.com/index.asp?Option1=cats&Edit=2&EditU=1&Regit=2
Smaller quantities are available on the Flea Bay. I started out that way but decided that I would spend more after
the shipping was added to each individual item, and for much smaller portions, than buying from that link.
But if you look on this link you can get 1lb quantities of pre-mixed in the proportions mentioned above it for
$10 per lb. Personally I think the pre-mix is heavy on KH2PO4 as I use a much smaller percent than what is listed on there.
http://greenleafaquariums.com/aquarium-fertilizer.html
 
#45 ·
How badly does the clay stain hands and nails? My other obsession is my nails. Honestly, I'd rather spend the money on root tabs than end up with stained nails. (I mean OPI has two new collections out!) I tried rolling out the clay, but that was not working at all. I ended up adding some water and mixing everything up while wearing gloves. It'd be so much easier if I could just get in there with my hands.
 
#46 ·
Oh my now that's a predicament you have. I know how much money my wife spends getting her nails done so I guess I can understand. It's pretty messy making these and does take some scrubbing to get it all off but I'm not as picky about my nails as I'm sure you are. I have a whole jar of these I made awhile ago but don't need them for now since I switched to Aquasoil.

By the way is it bad that I know what OPI is?
 
#54 ·
Love this idea...

But where do you get all the separate ingredients?

I mixed some ball clay (hit it with a hammer until it was dust) I had left over from my sculpture days into my dirt substrate along with the Miracle Grow Organic Compost and some expanded shale, then capped the whole thing with Floramax. Planst have been growing amazingly, no Co2 needed.

But I'll need ferts sooner or later... would like to make this!

So where to get the raw materials?

Also how do ferts in general impact your water quality, does it release nitrates, nitrates, etc into the water column?

Thx
 
#59 · (Edited)
Using root tabs is hit and miss. All the best tanks use water column dosing for ferts. It's more controlled and reliable. With root tabs, you have no idea how much is being released, and when. You're just hoping it somehow works out. Not the route I would recommend. Especially when water column dosing is so easy, cheap, and super well documented.

If you want something easy, try the root tabs. If you want something that will make your plants look good, forget about the root tabs and go with the tried and true method.
 
#60 ·
I found some great articles along the search for diy fertilizers such as this one and that one. But didn't find one entirely to suit my needs. One main thing I kept hearing is you can't add phosphates with iron. They will precipitate, etc. Some of the well known brands such as Flourish Tabs don't have Nitrates and Phosphates added.

This is my personal recipe:

1 cup micros
I start out with a hunk of clay about the size of a 3" square block and add as needed. (Amaco brand is the one I use. Whatever brand, it must be natural clay, not polymeyer)
4 tablespoons KN03
3 tablespoons MgsO4
3 teaspoons K2SO4
2 tablespoons of KH2PO4
1 tablespoon CASO4
Water to help mix

Optional:
Rolling pin or pasta making machine (or patience if you do this by hand)
Wax paper or other surface to roll out and store the tablets as they dry
Butter knife

Supplies gathered:


towel.



what kind of fert did you use?
garden fert?
 
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