Looking for cheap fertiliser recommendations.

[Vsevolod Stakhov]

am not sure if you need the additional K, have you tried without it? would like to see the results.

Well, after some experiments I consider Potassium as an element which just need to be sufficient and stable (most importantly stable, tbh). All experiments to reduce it has caused stagnation and algae. Increasing Potassium levels were not harmful at all (even at 100ppm in hard water). That's why I've decided to treat Potassium as a water mineralisation part: I just add some dry K2SO4 on water changes and forget about it.
I know that some people keep low potassium levels, like 2-3ppm. But my plants just don't like that from what I've observed in the past. I can say the same for Iron: that's why I had to replace one TEC-SF dose with pure Fe dosing and added extra Fe as well. When I've used pure TEC-SF without any additions I got quite a bad problems with red algae and plants health. The only suspection was that traces level were too high relative to Fe. After increasing Fe and slight decreasing of traces I got stable growth, good colours and no algae issues.
Again, with Solufeed TEC, the iron percentage is much higher relative to other traces, so presumably there is no need in additional Fe. However, EDTA is no option for a hard water tank: it disappears in hours at PH=7.5.

 

[John q]

"5ppm NO3 (equivalent) 0.7ppm PO4 and 2ppm K"
is what you said before. x3
that'll be 15ppm No3, 2.1 ppm Po4, and 6ppm K. quite far from standard EI. have you tried lowering the dose to maybe no3 as proxy 10ppm?

Title of this thread was cheap alternative fertiliser.... solution apparently is lean dosing.... 😕 again.

Suggest we answer the question, without deviation into dosing strategies 🙃

 

[GreggZ]

I know that some people keep low potassium levels, like 2-3ppm. But my plants just don't like that from what I've observed in the past.

In my experience that's true for about 98% of the plant growers out there. Plants love potassium.

Title of this thread was cheap alternative fertiliser.... solution apparently is lean dosing.... 😕 again.

Suggest we answer the question, without deviation into dosing strategies 🙃

LOL Agreed I have never seen as much obsession about lean dosing on any board or with any group of people before I came here........and I know a LOT of people in the hobby.

 

[John q]

have never seen as much obsession about lean dosing on any board or with any group of people before I came here........and I know a LOT of people in the hobby.

It's a phase, please stick with us 😀

 

[MichaelJ]

LOL Agreed I have never seen as much obsession about lean dosing on any board or with any group of people before I came here

LOL yeah, well... but seriously, it may appear so, but I think it's really a small minority on this board who are in on that particular discussion. Most here don't really care because whatever they do already works or they are not inclined to try out other approaches so they don't bother and that's all fine... lean is not for everyone as we have discussed previously. However, one could easily ague that it would be more appropriate to call out the Estimated Index die-hards as obsessive as those are the ones that always seems to trample in on the lean, or other alternative dosing discussions, with their opinion already set in stone and trying, mostly in vain, to contradict and falsify what the small group of innovative lean-regime folks evidently have shown is possibly - and most folks that do so haven't even tried it out or are not inclined to even try, so it quickly ends up being moot like a Ford vs. Chevy discussion 🙂

I am never in on very specific technical CO2 discussions because I don't think I have an opinion or insights that helps anyone. I am not a CO2 user and have never tried it, so walking in on a regulator discussion telling people that CO2 is a completely unnecessary complication to the hobby causing more trouble for more people than it helps or whatever misconception I may hold one way or another would be just as ridiculous as the aforementioned lean vs. EI discussion scenario, so I just limit myself to reading up on those threads and possibly learn something or get inspired.

Sorry about the rant - it's not directed towards you in particular @GreggZ - I've been off for a while, so I am still catching up!

please stick with us 😀

I agree... please stick 🙂

Cheers,
Michael

 

[Simon Cole]

Funnily enough I tend to get my fertilisers from quite unusual places. Surfy's Home Curing Supplies do the cheapest and safest potassium nitrate. They also have good ideas on how to cure your sausages and ham guys and gals.

 

[Happi]

Macro: Solufeed 2-1-4 - 75g per 1l, dosing 10ml/100l gives us 5ppm NO3 (equivalent) 0.7ppm PO4 and 2ppm K; I dose that three times per week as per EI dosage:
Micro: Solufeed TEC-SF (not TEC!) - 63g per 1l, dosing 10ml/100l gives 0.1ppm Fe + traces; I dose that twice per week
Fe: Solufeed FeDTPA - 8g per 1l, dosing 10ml/100l gives 0.1ppm Fe only; I dose that three times per week

15 No3 (3.4 N total)
P 2.1
6 K

You are only adding 7 ppm or so NO3 and remaining is coming from Urea. Truly you are not dosing EI, you are somewhere between the lean/medium. 3 ppm N weekly is what I usually recommend when it's combined with NH4 or Urea. 6 ppm K is sufficient as well, the P might be slightly excess but it will boost the plant growth especially when combined with Urea and bit of extra K. This fertilizer is designed for fruit and flowers and the ratio is designed for such yield, aquatic plant would be similar to grass and using a grass based fertilizer would be more appropriate. Any additional K will only buildup overtime and it won't happen over night. Meanwhile several plant will continue to grow fast, especially most stem plants. If you were to add rotala wallichii in there, it will continue to do well mainly due to Urea.

 

[Vsevolod Stakhov]

This fertilizer is designed for fruit and flowers and the ratio is designed for such yield, aquatic plant would be similar to grass and using a grass based fertilizer would be more appropriate.

The mobility of N in soil is much higher due to different processes, e.g. denitrification which just wastes like 30% of N from fertilisers. I think that's the main reason why N content in fertilizers is much more than in KNO3 salt (which is exactly the form how the higher plants store nitrogen in their cells for further usage).
Furthermore, terrestrial plants can extract P and trace elements from the insoluble compounds (e.g. using anaerobic conditions + low PH in xylema). Aquatic plants can hardly do it counting that we usually have quite a thin layer of substrate comparing to the natural conditions.
That's why I still think that "high K" agriculture fertilisers are actually more suitable for the aquatic plants. Extra K will just be removed by water changes, as usually.