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Low tech and EI ferts

Joined
13 Feb 2020
Messages
111
Location
Wexford,Ireland
Hi, I have a few low tech tanks set up along with my higher tech that i dose with EI. I was just curious that if i ever wanted to add ferts to the low tech tanks once in a while, what would be the best to dose it with? Micro or Macros?
 
1/5 to 1/10 is standard dose once a week or two. Dose both micros and macros. All in one fertz like TNC Complete are cost effective at low doses, dry salts even more so.
Or you can use Darrel's Duck Weed Index if you have floaters, if you don't perhaps think about getting some.
Either way checkout Tom Barr's Non CO2 Methods
 
what would be the best to dose it with?
I don't think it's an either or situation, the plants need "some of everything" you could get away with just micros, something like Tropica Premium which is just traces but that would largely depend if the plants were getting some npk macros from somewhere else like the fish waste or your tap. Salts are a far cheaper alternative.
I generally dose about a third EI in my low energy system all in one day on water change day then divvy the same dose up into 3's and dose it every other day the second week before changing about 40% of the water fortnightly which seems to work for me. It's slightly higher than the Tom Barr article @Tim Harrison referenced at the bottom of his post but I have low fish stock levels (mainly shrimp with a few fish), I have floating plants and house plants with roots that trail in the water (both will chomp through ferts I would guess) and use harvested rain water (which will pretty much contain nothing along the line of nutrients.

The duck weed index mentioned may help identifying if there is something missing but if your plants are healthy maybe it's not worth fixing? If anything Micros with a little bit magnesium sulphate in the form of epsom salts might be the first port of call and look for an improvement in general plant health.
 
I have been using Tropica specialised ( the green one) in my no co2 low tech tank and it is really efficient and cost effective. I have found it to be too potent and I now use one pump for a 100 litre tank once a week!
 
Interestingly a while ago John at APFUK in a article said he didnt recommend EI for a low tech but knew there were calculations for dosage
 
Hi all,
John at APFUK in a article said he didnt recommend EI for a low tech
I assume that is because the plants are carbon and/or light limited, so they can't make use of that level of fertiliser. As you drop the dosing rate, and/or frequency of dosing, down you are eventually going to arrive in the "Goldilocks zone" where there is the right level of <"some of everything">.

I don't think it really matters how you get there, you just need your plants in active growth.

cheers Darrel
 
Is there a downside to having excess of nutrients in a low tech, beyond costs? Similarly is there a downside to having water changes at similar levels to a high tech?

I'm running a low tech for my son, and auto-dosing daily as its just easier to administer with the auto doser, plus the auto-water change schedule is still the same from when it was set up as a high tech (25% daily). The dosage is much lower that standard EI (maybe just under 10th of EI).

I will reduce things slowly over time, but wondered if there is any specific dis-advantage for doing this on a low tech system a low tech system?
 
Hi all,
Is there a downside to having excess of nutrients in a low tech, beyond costs?
Some people <"will tell that there isn't">, personally I'm not sure and would rather have low levels of nutrients.

My guess is that plant growth is the important thing, and that as long as you have plant growth (and you aren't adding toxic amounts of ammonia etc.) not a lot else really matters that much.
Similarly is there a downside to having water changes at similar levels to a high tech?
No, I don't think there is. I always had fish issues <"before I understood about the importance of water changes">, since I've been a regular water changer fish health has improved immeasurably. I've always used rainwater, so I don't have any experience of large volume water changes with tap water.

cheers Darrel
 
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Is there a downside to having excess of nutrients in a low tech, beyond costs?
Don't open that can of worms :D The reduced EI model sort of works for me using the assumption that each element is going to be consumed by the plants in those kind of ratios so it's simpler to divide them ratios when dosing and be fairly confident you are somewhere near. For instance 1/3 n also match 1/3 p etc. I use rainwater but the same would apply to RO, beyond that we don't know for sure what's coming out of the tap if you use tapwater so the ratios breakdown at that point, also fish waste needs taken into account. In a low energy system you get far more room for manoeuvre as issues tend to happen slower, that's where the Duck Weed Index comes in to play, DW is closest to the light source and has unlimited co2 and reacts quickly to a lack of nutrients giving you time to dial it in before the other submerged plants start to suffer. The hard part is working out which ones!

Or not as the case may be, you just have to take an educated guess at where your particular tank needs to be. What we do know for sure is the plants do need "some of everything" or look at it as a balanced diet in human terms. We also know that EI dosing is in excess of what could possibly be consumed, now it's about finding out where our tank sits between those two points. ( This changes as plant mass increases) Leaving the excess nutrients and possible if any pitfalls aside you can work backwards using the DWI as a constant in tank monitor to let you know when you've reduced down too far. The ideal being just slightly more than you need so the plants never become deficient. In my case that's why I go a little higher than Tom Barr's suggestion because of the other mitigating circumstances I mentioned earlier in the post.

Back to the OP's post. Because they never came in with an issue it sounds like they are already somewhere near the sweet spot already. Traces and Magnesium could give an improvement in overall health as these are the things that you can virtually guarantee will be missing because the traces are generally stripped out of the tapwater and it's very rare to get Magnesium out of the tap in the UK. That's not to say the OP could be getting these from either a soil substrate of some kind or in something they are using to raise the hardness of the water. Each tank is as different as you are, that's what makes them the same :D


Similarly is there a downside to having water changes at similar levels to a high tech?
My own personal experience and that's just based on my current setup is when I was changing weekly some plants didn't do so well, Crypts in particular. When I changed to every two weeks and sometimes longer they seemed to improve. Purely anecdotal but I'm thinking maybe crypts don't like changes too often. Crypts are notorious for melting back when in different conditions especially newly planted. I could be putting 2 and 2 together there though and getting 5
 
Is there a downside to having excess of nutrients in a low tech, beyond costs?
At one time adding fertz was thought to encourage algae and then along came Tom Barr with EI and pretty much proved that it didn't. Now there seems to be a move toward lean dosing. The low-energy tanks that worked well for me were lean dosed soil substrate tanks with a lot of the nutrients locked up in the soil. I found that method gave me much more wriggle room, in terms of playing with lighting to get the growth I was after, without algae becoming a problem.
Similarly is there a downside to having water changes at similar levels to a high tech?
I'd like to say I changed the water frequently but in those tanks it was probably 50% every couple of weeks or so, sometimes longer once they became established.
 
Thanks guys - I should probably look to cut back on the ferts then. AFAIK my tap water has sufficient N (18mg/l from the water report), K and Mg (I'm in an area where Mg is present in the tap water), and I guess a fair bit of N and P will be added via fish food/waste. If I'm changing water every day currently, is it likely the tap water will be providing sufficient micros also?

The plants are mainly anubias, crypts, ferns and some Buce, so all very slow growers other than a bit of eleocharis and lilaeopsis brasiliensis at the front.

 
Hi all,
If I'm changing water every day currently, is it likely the tap water will be providing sufficient micros also?
Iron (Fe) is probably the most likely to micro-element to be "missing" (probably just unavailable), which is partially why I've gone to using a <"hybrid duckweed index">, where I add iron and magnesium (Mg) <"on a regular basis">, but don't add any other fertilisers until the <"Frogbit indicates that I need to">.

As you say you live in the part of the UK where you have some magnesium in the water and you are also more likely to have most of the trace elements <"for the same geological reasons">. Trace nutrients are likely be more common in water from aquifers that <"contact evaporite deposits">.

These evaporite rocks are formed where a large volume of sea water has evaporated, concentrating the solution and forcing the dissolved ions out of solution.

cheers Darrel
 
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Iron (Fe) is probably the most likely to micro-element to be "missing" (probably just unavailable)
In my particular case PO4 is added to the tapwater supply at the treatment plant possibly for raising alkalinity? as our water is extremely soft. AFAIK this would then react with the iron forcing it to precipitate and get filtered out. Not sure if this is common practice in all softwater areas of the UK.
 
and I guess a fair bit of N and P will be added via fish food/waste
From what I've read and because lighting these days is very efficient (Even the ones we class as low energy because they use low watts but still achieve reasonable par to watt) fish food adds very little nutrients. I would suggest it would take quite a high fish stock and combined heavy feeding to make a real difference. The downside being along with the nutrients from feeding you also get other waste bi-products which aren't helpful=more water changes.
 
Hi all,
In my particular case PO4 is added to the tapwater supply at the treatment plant possibly for raising alkalinity? as our water is extremely soft. AFAIK this would then react with the iron forcing it to precipitate and get filtered out. Not sure if this is common practice in all softwater areas of the UK.
Yes, most UK <"tap water is treated"> to raise the pH and has phosphate added to <"precipitate out any heavy metals">.

Those metals <"would include iron"> (Fe), even though that isn't the main target. Water companies will aim to reduce levels of iron (and manganese (Mn)) in tap water for <"aesthetic & taste reasons">, often just by oxidation. In the cases of @Wookii and @Angelfishguy99 they have hard tap water so need <"an efficient chelator"> for iron.

cheers Darrel
 
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