Converting Low Tech Tank Ferts from TNC Compete to DIY?

Mark.A

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Hey all! Looking for advice on how I can best change my dosing over from TNC Complete to DIY Salts for my low light/low tech tank. I know EI was designed with high light/high tech tanks in mind so I want to figure out what I would need to dose to roughly equal what I am dosing now with TNC Complete and maybe what I can safely increase/decrease from there.

I am currently dosing 5ml per day of TNC Complete into my 123 Litre low light/low tech tank via a dosing pump. It is very heavily planted with a full Helanthium tenellus carpet, loads of moss, java fern, various Anubias, various Bucephalandra, few different stands of Crypts a Crinum calamistratum and some Ludwigia sp. mini 'Super Red'. The only plant that grows fairly quickly is the Ludwigia, although the mosses, Crinum and carpet are not far behind.

I have very little algae, just a slight sprinkle of green dust algae on top of some of the rockwork, which I actually quite like. I have no deficiency issues at all with the plants, they all grow healthy and look good.

The reason I want to switch over to DIY salts is cost, not really for this tank as it's not that expensive using TNC Complete for this tank but I'm about to set up a second tank and another larger third tank will be coming after that one, hence the interest in switching to DIY salts. All three tanks will be low light/low tech so the nutrient requirements should be pretty much the same per litre so I figured I'd get to grips with the dry salt mix now before I start the second tank.

Things to consider:
My tank is heavily stocked and I feed heavily so N+P may not need to be dosed as high and can probably come down from what's in TNC Complete. I will test the nitrates/phosphates before my next water change and give you the exact figures. I also have 2.5 ppm PO4 in my tap water but only a slight trace of nitrates.

Questions I have:
1 - I've seen the ' All In One Solution' for dosing all the salts in one solution - if this works and you can just dose everything in one solution without issue then why isn't everyone doing this? Is there a downside or reason not to do this? Would you recommend it?

2 - I've seen somewhere before that someone was dosing the salts separately but within the same day so the tank was getting everything every day rather than alternating macro/micro nutrients on different days. Is this a thing and if so is it better? Does it make any difference? Would you recommend it?

3 - Where is the best place to get the dry salts in bulk in the UK?

4 - Is there any reason not to make larger quantities, like 5 litres of the macro/micro nutrients?

5 - Can anyone recommend decent looking containers to hold the 5 litres of nutrients?
 

zozo

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I'm currently having low tech setups only and dose dry salts directly into the aquarium after a water change...
And then only if the plants in it tell me it's necessary. :) Some low tech setups, depending in their age and plant species can be pretty self-sustaining without adding any ferts. For example, i have a low tech tank with Anubias, crypts, valis, java fern and a lily and some mosses. And i rarely dose it with ferts... If i do, the valis goes bonkers and out of control.

The other tank is more like a paludarium setup with a load of emersed growing plants, this is the only one that gets a fert dose after each water change.

For me, it's pretty simple i use a calculator to find the correct amounts of dry salts to reach the proper PPM value. Then i have a 0.01 pharmacy (jewellers) weight scale and a scoop.
http://theaquatools.com/fertilization-calculator/

Add Aquarium volume, directly into the aquarium is set to default. Then fill in the number of grams of the salts you have.
At the bottom, you see a reference of good values and how many PPM you added, keep adding grams till you are at a good value.

Knipsel.JPG

Only used the weight scale a few times, by now i know my scoop (1/4 teaspoon is 1.9grams of either salt), do a water change then take a jar to fill it with water and scoop in the salts i need. Stir it and drop all in the tank. And that's all to it.. :) 24 hours after i add the Micros.


I found this the easiest way to get around it... For me personally having the salts at home on the shelf it makes no sense to create a solution in a bottle next to it and dose it as a liquid. It's to much hassle and takes up to much time and space. I like to keep life as simple as possible.. :thumbup:
 
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TNC Complete contains 1.5% Nitrogen, 0.2% Phosphorus, and 5% Potassium. Therefore in your 35ml per week you are adding:

0.525g Nitrogen, which is 2.325g nitrate, i.e. 19ppm per week
0.07g Phosphorus, which is 0.2g phosphate, i.e. 1.7ppm per week
1.75g Potassium, i.e. 14ppm per week.

If you’re buying potassium nitrate (KNO₃), monopotassium phosphate (KH₂PO₄) and potassium sulphate (K₂SO₄), I would make up a stock solution as follows:

In 500ml, dissolve 64g of KNO₃, 5g KH₂PO₄ and 6g of K₂SO₄. From this stock solution, dose 10ml three times a week. If you want to use potassium bicarbonate (KHCO₃) instead of the K₂SO₄ then you’d dissolve 7g into the 500ml stock solution.

This takes care of your macro fertilisers. You will also want a source of micro. TNC Complete contains 0.08% iron, so in your 35ml per week you’re adding 0.028g, i.e. about 0.23ppm per week. If you use TNC Trace, I think the standard dose of 1ml per 10 litres will give you this, and I’d split it into 3 weekly doses and dose on alternate days in between the macro doses.
 

dw1305

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Hi all,
If you’re buying potassium nitrate (KNO₃), monopotassium phosphate (KH₂PO₄) and potassium sulphate (K₂SO₄), I would make up a stock solution as follows:
Dry salts are definitely the way forward, unless you have a very small tank.

It also allows you to tailor your mix for your particular circumstances, a long these lines you probably need a magnesium (Mg) source as well. "Epsom Salts" (MgSO4.7H2O) are ~10% magnesium.

cheers Darrel
 
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It also allows you to tailor your mix for your particular circumstances, a long these lines you probably need a magnesium (Mg) source as well. "Epsom Salts" (MgSO4.7H2O) are ~10% magnesium.
Good point! I use a stock solution of 44 g/l and use it to tweak my GH at water changes. 1ml per litre of this raises GH by 1°. Happily this also gives me a reasonable Mg level.

I bought a 10kg tub off eBay. By my reckoning this will last me about 175 years. (But I also use it to prevent dark spots forming on Photinia leaves, and I often throw it randomly around the garden.)
 

Simon Cole

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2 - fertiliser compatibility - yes it's been talked about ever since Dennis Robert Hoagland started work on a combined fertiliser in the 1930's. You can find a few examples of fertiliser compatibility charts if you search on the internet. The primary reaction people fear in aquariums is that Fe EDTA will react with phosphorous in the presence of light. When an insoluble compound forms (like calcium phosphate or calcium sulphate) it prevents enough mobility to allow this to be taken up by plants. A problem that typically faces land fertigation is the reactions of certain ions with ammonia and sulphate salts.

3 - I buy salts from allover the place. You can usually buy reasonable amounts (10 or 20kg) of KNO3 from salt curing companies. I do. You can buy several hundred kilograms or even tonnes of all of these fertilisers at very little cost from agricultural suppliers and fertiliser companies, and 60kg or 100kg bag of chelated trace elements will last quite a while. The thing about traces is that they are all slightly different - so you are going to have to think about what constituents you really want. Over the years various ratios have been suggested and that may influence what you choose to mix (e.g. P:Zn, Ca:Mg, Fe:Mn). Some are disputed - little research has ever been done for specific aquarium plants.

4 - yes. It is quite hard to keep fertilisers stable. and 5. I use kilner jars housed in the fridge. You will notice crystal formation is quite common when solutions are left for a while.
 
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Simon Cole

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I should add Mark that I am quite dubious about the EI ranges, just slightly dubious about "complete mixes". I don't really have enough time to study the complex chemistry behind it all. I welcome the idea of using plant leaf dry mass spectrometer analysis to work out plant requirements, but until I see validated evidence, I will assume that most of the assumptions under EI are unproven speculation... or at best, specific to one plant species. I am in the camp that does not support EI dosing because I do not see what it has achieved. Tests against Hoagland's solution are more robust. If EI seeks to re-brand this then I generally call it Hoagland's solution (HS). If however, it is valid then it must be scientifically validated. I think complete mixes probably do work to some extent. But they would not be my preferred storage solution.
 

Witcher

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1 - I've seen the ' All In One Solution' for dosing all the salts in one solution - if this works and you can just dose everything in one solution without issue then why isn't everyone doing this? Is there a downside or reason not to do this? Would you recommend it?
I can explain why I'm using separate salts instead of all in one by this example from my tank (relates to other fussy plants too, but problem is quite similar):

macrandra_pinna.jpg


To get macrandra really deeply pink-red I need to keep Nitrates below 5ppm. If I'd use all in one solution and try to lower Nitrates to that level, other nutrients levels will be automatically lowered as well (including Potassium) - and hygrophila pinnatifida will very likely develop tiny holes in the leaves (K deficiency) - so the only way to please them (and my eyes too) is to keep ferts as separate solutions and dose what's needed depending on the plants. BTW many red plants require lower levels of N than green plants, while they need more Phosphates - so possibility of balancing ingredients is really helpful.
 

hypnogogia

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@Witcher do you mix you own desperate macro and micro, or do you dose individual salts? If the former, may I ask how much of each salt goes into your macro mix? I ask as I want to reduce my nitrates (nitrates in tap water) but still need to dose K.
 

Mark.A

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I can explain why I'm using separate salts instead of all in one by this example from my tank (relates to other fussy plants too, but problem is quite similar):

View attachment 150556

To get macrandra really deeply pink-red I need to keep Nitrates below 5ppm. If I'd use all in one solution and try to lower Nitrates to that level, other nutrients levels will be automatically lowered as well (including Potassium) - and hygrophila pinnatifida will very likely develop tiny holes in the leaves (K deficiency) - so the only way to please them (and my eyes too) is to keep ferts as separate solutions and dose what's needed depending on the plants. BTW many red plants require lower levels of N than green plants, while they need more Phosphates - so possibility of balancing ingredients is really helpful.
Yeah, I get that. The 'All in one solution' I was on about is still mixing DIY salts but mixing them all together instead of separate macro and micro nutrients so you only have to dose one solution. You could still adjust each of the nutrients up/down individually within the mix.

See here for details: All in one solution
 

Zeus.

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Is there any reason not to make larger quantities, like 5 litres of the macro/micro nutrients?

Yes, you can get mould growing in them. best if fert is made and used in 4-6 weeks. Which is why (if it suits) dry salts is a winner IMO.

We are in the final stages of the next release of the latest Fert Calculator which does dry salt dosing, clone commercial ferts, multiple tanks which should make DIY ferts a breeze. The present V1.8 isnt to shabby either ;)
 

Mark.A

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Yes, you can get mould growing in them. best if fert is made and used in 4-6 weeks. Which is why (if it suits) dry salts is a winner IMO.

We are in the final stages of the next release of the latest Fert Calculator which does dry salt dosing, clone commercial ferts, multiple tanks which should make DIY ferts a breeze. The present V1.8 isnt to shabby either ;)
Dry salt dosing is not for me. I prefer dosing the solution plus I have already invested in dosing pumps. First time I've heard of the DIY salt mix having to be used in 4-6 weeks, that's disappointing. Is there no way to avoid the mould and have the mix last longer? I know with the TNC Complete people buy the 5 Litre drums of it and have it dosing for a year or more. Can't you do this then with the DIY mix?
 

zozo

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Mould is a result of not working clean... :) I bet it can be reduced with disinfection... Not using tap water but Deminarilzed water instead. Add the salts and then add a % H2O2 into the bottle it will react to anything organic in there and kill it... Additionally adding something mild acidic could help as well. But a properly closed sterilized bottle/canister can do quite some time without...

I guess it can be done with tap water too, disinfect it... But since you are adding salts and if you don't want to calculate whats already in the tap water. Rather use Demi Water instead... From experience for example, the water company lab report states >20ppm nitrates in my tap water... Thus 20ppm is a minimal in my case without adding anything... :cool:
 

Witcher

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Is there no way to avoid the mould and have the mix last longer?
@Mark.A You can use boiled RO/distilled water for mix, this will not only make many salts dissolving quicker, but also will kill some bacteria/fungus causing certain types of mold. Plus it's worth to buy analytical/lab grade salts instead of the ones for gardening etc. Disinfection @zozo mentioned will also help.
@Witcher do you mix you own desperate macro and micro, or do you dose individual salts? If the former, may I ask how much of each salt goes into your macro mix? I ask as I want to reduce my nitrates (nitrates in tap water) but still need to dose K.
@hypnogogia I have individual salts dissolved in separate bottles plus some kind of N (CaNO3/KNO3/MgNO3) and K (KCl, K2SO4, KHCO3) boosters.
My dosage weekly is for whole tank (although not coming from mix but from individual bottles):
Between 4-8ppm K (KHCO3+KNO3)
Between 5-9ppm NO3 (KNO3 plus booster sometimes)
Between 4-8ppm PO4 (KH2PO4)
2ppm Mg (as mineralisation of RO with MgSO4, CaCl and KHCO3 - these go to water change container as dry salts).
Fe at approx 0.1 - 0.15ppm
Of course above may change depending on the situation in the tank but these are the ranges I generally use.
 

zozo

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Yup it actually isn't rocket science, maybe not for a kitchen princess like me... :hungry::shy:

When I make my Jams from whats growing in my garden... Disinfection of the jars is key to enjoy it for years to come.

Why should it be any different with storing fert solutions... ;)

Cook it!!! ;)
 

Zeus.

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Adding 1.0 gram Ascorbic Acid (E300) and 0.4 gram Potassium Sorbate (E202) per litre is what James Planted Tank found to work well for his All In One fert. Which I do use on my Macro and Micro fert mix and a TNC clone I have been using, which does seem to keep the mould at bay. However I do only mix about 6- 8 weeks of macro/micro mix at a time and only did my TNC clone recently so cant really comment on how well the Ascorbic Acid and Potassium Sorbate helps for at least another 11 months. But James does say it worked well for him.
 

Geoffrey Rea

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To get macrandra really deeply pink-red I need to keep Nitrates below 5ppm. If I'd use all in one solution and try to lower Nitrates to that level, other nutrients levels will be automatically lowered as well (including Potassium) - and hygrophila pinnatifida will very likely develop tiny holes in the leaves (K deficiency) - so the only way to please them (and my eyes too) is to keep ferts as separate solutions and dose what's needed depending on the plants. BTW many red plants require lower levels of N than green plants, while they need more Phosphates - so possibility of balancing ingredients is really helpful.

Really great post @Witcher you explain why both Pinnatifida and Macrandra tend to cause a lot of people a headache. Your post really deserves its own thread, as pretty sure there will be people searching for solutions on here, your answer is very succinct.

Somewhat lacking your finesse, my solution is to use leaner aquarium soil with root tabs under all the other species and then run the water column lean of nitrate.

Discussing this with Filipe and it’s pretty much the same routine he used on his last Pinnatifida heavy IALPC entry, although his motivation was to slow growth to minimise maintenance as he travels a lot.
 

dw1305

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Hi all,
To get macrandra really deeply pink-red I need to keep Nitrates below 5ppm. If I'd use all in one solution and try to lower Nitrates to that level, other nutrients levels will be automatically lowered as well (including Potassium) - and hygrophila pinnatifida will very likely develop tiny holes.....
Somewhat lacking your finesse, my solution is to use leaner aquarium soil with root tabs under all the other species and then run the water column lean of nitrate.
Perfect, that is what I suspected in the <"anthocyanin post">, but I've never really grown any <"red plants successfully">.

cheers Darrel
 
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