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Ei ferts on a low tech

I tend to use 1/5 to 1/10 typical EI dose.
If you're using dry salts the standard regime, for say a 20 gallon low energy tank (a la Tom Barr) is to dose once every week or two with the following; 1/4 teaspoon of GH booster, plus 1/8 and 1/32 of a teaspoon of KNO3 (potassium nitrate) and KH2PO4 (monopotassium phosphate) respectively. The ratios can be scaled up or down to suit any size of tank.
 
I looked at daily EI values dosed for my size tank and high tech CO2 injected tanks daily, and add this amount once a week, or every other week in my low tech tank's.
Currently dose 80 gal low tech with
3/4 tsp KNO3
1/2 tsp K2SO4
1/4 tsp KH2PO4
1/4 tsp CSM+B
1/4 tsp Iron from DTPA
Dose once a week or every two week's.
Weekly 50% water changes like I have for year's.
 
I've dosed 1/3 recommended ei dose 4x a week (2macro 2micro) on some of my low techs, if you have a TDS meter you can gauge if the plants are using most of the nutrients added.

Sorry to go off topic on this one but I've heard this mentioned on numerous occasions especially when related to Darrels duck weed index. Does anyone have any links to an in depth explanation on how you would carry that out or could explain please? It's something I'm interested in doing but couldn't work out how to decipher the TDS readings. My assumption would be that you could use the readings before and after dosing and if they weren't going up by x amount you could somehow gauge the amount of ferts the plants were using. However, how could you take into consideration the other things like waste and say for instance rock that was dissolving carbonates into the column?

I guess this is still on topic a bit, I'm looking at setting a low tech/soil tank up shortly mainly using various crypts and was wondering how I can gauge what sort of amounts of ferts I would dose based on something obviously more than using the plants as indicators. I guess as good as a method it is the problem being if you do see deficiency in plants then the damage is already done and they will need time to recover. That throws up the quandary of am I now dosing right or are the plants still recovering from the last time I wasn't.
 
Currently dose 80 gal low tech with
3/4 tsp KNO3
1/2 tsp K2SO4
1/4 tsp KH2PO4
1/4 tsp CSM+B
1/4 tsp Iron from DTPA
Dose once a week or every two week's.
Don't dose DTPA and KH2PO4 together as the iron will react with the phosphate and precipitate out as insoluble iron phosphate, making both iron and phosphate unavailable to plants.

Just dose DPTA on alternate weeks if low tech.

My mate has run a low tech tank for years dosing 1/4 dose alternating macro & macro once a week. His tank is largely algae free and has slow growing plants. He is happy with the low maintenance schedule.
 
1/3 EI
Don't dose DTPA and KH2PO4 together as the iron will react with the phosphate and precipitate out as insoluble iron phosphate, making both iron and phosphate unavailable to plants.

Just dose DPTA on alternate weeks if low tech.

My mate has run a low tech tank for years dosing 1/4 dose alternating macro & macro once a week. His tank is largely algae free and has slow growing plants. He is happy with the low maintenance schedule.


Yes,^^ I dose the CSM+B and DTPA once a week or two as mentioned ,but day after dosing macro's.
My bad for not being very clear,
 
Dosing 1/3 EI values is more than would be achieved naturally via fish waste and fish food's, in low tech NON CO2 but who is to say one can not dose 1/2 EI values weekly or every other week and adjust from there?
Is what I did.
My experience with Duckweed which I have gob's of,is that so long as I am netting some out each week, that nutrient's are driving the growth.
When the duckweed begin's to look poorly ,and development drop's off,that is indication to me anyway that maube nutrient's are lacking.
Don't know which nutrient's ,,so I add more of everything.
 
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Hi all,
Sorry to go off topic on this one but I've heard this mentioned on numerous occasions especially when related to Darrels duck weed index. Does anyone have any links to an in depth explanation on how you would carry that out or could explain please? It's something I'm interested in doing but couldn't work out how to decipher the TDS readings.
It isn't an exact science.

You do a relatively large water change (with your tap water, assuming that you use this) and then measure the TDS. This is your baseline level.

You add the dose of 1/3 EI etc. measure the TDS again (you can do this after a couple of minutes even if you add dry salts, because the fertilisers are soluble and they will have gone into solution as ions pretty much straight away). Next day measure the TDS again, it should have dropped a little bit, keep on measuring it until you are back to somewhere near your baseline level, then add another dose of EI. I do small volume daily water changes, but you can use whatever water change method you like.

Assuming your plants are growing acceptably just carry on like this. I'm lucky in that my tap supply comes from a deep limestone aquifer and is pretty consistent (the dissolved salts are ~90% Ca++ & HCO3-), if you have a supply with more surface water in it you may find more of range of TDS values for your tap water during the year (lower in winter with more rain-fall, higher in the summer with more agricultural fertiliser run-off and a greater contribution from waste water etc.)

Some TDS bits
The TDS meter measures conductivity and then uses a conversion factor (0.64 usually) to estimate the TDS from the conductivity reading (64 ppm TDS = 100 microS).

The conductivity is just a measure of all of the ions in solution.
However, how could you take into consideration the other things like waste and say for instance rock that was dissolving carbonates into the column?
The TDS will rise a little bit from evaporation etc. but it shouldn't be a dramatic rise.

If you have hard water from the tap, and/or coral gravel or lots of limestone rocks in the tank, (a high dKH) you will have a high baseline TDS value (~400ppm TDS), but no more calcium carbonate (CaCO3) will dissolve from the rocks, unless the carbonate hardness falls dramatically (you add a strong acid etc). This is because carbonate solubility is regulated by the level of dissolved CO2 (which is dependent upon atmospheric CO2 levels in a low tech. tank).

If you have a soft tap supply and limestone rock etc your TDS will rise relatively slowly over time, which you would need to factor in. The pH of your supply water will be above pH7 (from the NaOH added by your water company), but the contribution to the TDS from the Na+ and OH- ions will be small, because NaOH is a strong base.

cheers Darrel
 
It isn't an exact science.

I strongly suspected that was going to be the case as for everything in this hobby. I find the mantra of the plants will tell you to be the most reliable but it's always good to have some information.
What made me ask was in my main EI dosed tank after not checking for many months (laziness) I found that my GH was 11, KH 4 and TDS of 320, now if I remember my tap water has no measurable gh/kh and a TDS of around 34 last time I checked and I do 50% WC weekly. Conclusion, there's far too much of something going in. I don't use any hardening products so I have to assume that the GH being far higher than the KH is probably from the mag sulphate so as a first port of call I have reduced that which I only add on WC day. The KH must be coming from the seiryu stone in the tank although when I test at start of week and end the kh has only raised by half a degree or thereabouts. Can't work out how that comes about, common sense would dictate that after 50% WC the KH would half but it doesn't seem to do that rather it drops a degree. Maybe I have more water volume than I think.

So based on the DWI this week after WC I test the tank then add the ferts, test again then probably next morning before dosing again look how much has dropped since dosing the previous day and taking into account that some of this will be fish waste and carbonates from the stone the figure would be how much got consumed is that correct? Obviously the figure I obtain will be slightly higher than in reality got consumed because of the increase in TDS from the other things mentioned. I hear dissolved co2 would also make a difference so probably best testing without, ideally before it was running although I suspect that would be negligible.

The reason I ask is two fold, I have some Rams coming tomorrow and would like to get the TDS down without affecting the plants too much so I'm looking to see where I could get and still maintain healthy plants. Plus I'm going for a wander in the lakes tomorrow to see if I can get some stone and if possible some wood for a little project I fancy. I have a 600x300x300 tank sitting empty in my office with a 450mm long led unit (cheapy off ebay) a Koralia and a 25ltr fermenting bin full of cat litter from some previous tanks. I've been doing a lot of reading in UKAPS about low energy soil tanks and it has me intrigued. The way I see it I throw lots of cuttings out so I'm only a bag of soil and some mesh investment away from seeing what could be achieved without a filter just using my cuttings, nothing to lose. Using the DWI/TDS method will be beneficial in both circumstances I reckon and give me a better understanding of what's going on in the tank albeit just some rough figures.

The best of it was I ordered a portion of DW off ebay as a bit of an impulse buy and never thought about asking in here if anybody had some for sale. Searched for Duckweed Index in the forum first post I came across was Darrel telling someone who throws all his extra DW out that he keeps his in ice cream tubs on the window! Doh :facepalm: It doesn't end there, I was going to cancel the ebay order but thought no, I bought in good faith and I'm not a tyre kicker so I'll leave it but when I checked the Sellers details I found out they actually live about 40mins drive away from me, double Doh :facepalm::facepalm:

Just left it getting delivered next week, wasn't worth wasting my fuel :D

Sorry I asked

Yeah sometimes it's best not to, you just get bogged down in detail. :D I suppose you're better off knowing though even if it confuses you more. I felt the same way when I had just got my head round putting loads of ferts in to make sure there wasn't a lack of anything only to find that too much of one can cancel out the other, every day is a school day in this forum.
 
Hi all,
Sorry I asked
Get away with you, it is quite straight forward.

I started measuring the conductivity because it was the only parameter that I could measure easily (and quickly) with a dip meter. From <"Best way to cycle....">
I'm not anti-testing, quite the opposite, I'd really like to know all the parameters for the aquariums, and it was the difficulties in getting repeatable results that first led me to looking at other methods for estimating water quality. The only dip meter, or test kit, that I could find that gave repeatable results over the whole range of water conditions, without constant re-calibration or sample preparation etc, was a conductivity meter. Conductivity isn't the measurement you would like, but you can use it to get a datum for your water.
Subsequently I realized that, because the datum for every tank would differ, that the <"duckweed index">, using Limnobium, was a more sensitive diagnostic, and I rarely measure conductivity now.

The only real flaw with the duckweed index is that by the time you see a deficiency of a non-mobile nutrient (nearly always iron Fe), you are going to have a reasonable amount of time before the plants recover, even after you've added plant available iron. I've got better at <"recognising iron deficiency"> symptoms.

cheers Darrel
 
You know what, I've just had an epiphany :wideyed: I've halved my mag sulf on the last two water changes from my usual 2tsp hoping to address my suspected GH rise. I've noticed this last week quite a big increase in algae on the glass which the ottos are loving right now (first time I've seen them all in a while) I had put this down to a filter clean and with it being sunny lately maybe a bit of excess light from a nearby window. Did I not read somewhere that high magnesium can stop Iron and that if your tank is deficient in iron as soon as you add some algae and plants will green up? Connected possibly?
 
In my personal view after caring for the Ram's for approx. four year's..Next to no hardness,and or TDS will yield best result's.
My water from tap used in all tanks is 12 dgh and pH between 7.4 and 7.6.
This water was not suitable is seem's.
So I set up small 20 gal tank and bought five gal jug's of distilled water and cut the tap water by 50% with the distilled water.
Much better result's.
Fully prepared now to hear from those who are able to keep these soft water species in Portland cement.
Also discovered that live blackworm's,cherry shrimp were favorites over flake and or pellet.
 
I'm quite lucky regarding soft water species as my water is extremely soft...or it would be if I didn't have to add so much salt to keep the plants happy.
Hopefully I can find the fine line between the fish, the plants and my lighting. I have the option of dropping the lighting to 50 or 25% if needs be. Not sure how some of the red species are going to take to that but the fish get priority really. I know it's a dangerous game lowering ferts unless you're a big fan of algae but using the tds method and monitoring the plants will take some of the guess work out of it.
As Darrel said not exact science but some information is better than none when making decisions.

Sent from my STH100-2 using Tapatalk
 
Haha wrong man to talk to brother. I've had some monumental cock ups when it comes to TDS meters. I bought one that was dual with a ph meter then found out it was for higher tds levels than we work with, then I bought another and found out you couldn't calibrate it. I sort of gave up after that, the one I have you can't calibrate is fairly new and factory calibrated so I'm going to use that. It probably won't tell me the exact tds but hopefully I can still measure the drop.

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"I've got better at <"recognising iron deficiency">"

Darrel I thought you were a scientist working in the plant industry? if you can't spot a plant deficiency you need to take a hard long look at your life and wonder what went wrong ;)

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