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How much fertiliser should I dose?

HBomb

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Brentwood
Hi All.
This is my first time posting on here and I could really use some help. My tank has only been set up for a few months now as I have had to restart a few times because algae got out of hand. This is the most success I have had since I got into aquascaping about two years ago. Although my plants are now growing and they have a lot of roots I don’t think they are thriving, and the algae will still take over eventually if I don’t do a good scrub regularly.
I can’t help but think it could be better than this. Since I have never experienced a balanced aquarium I don’t know.
As you can see from the photos I am struggling with green spot algae and blackbeard algae is starting to appear in places. The tank is about 100l with a sump so a total volume of 120l of actual water. I have recently added 3 Otto’s and 4 Amano shrimp but have ordered some more. Also have: 7 Rasboras, 4 Corys, 4 Rummynose Tetras and 1 Hongkong plec. My lights are on an 8 hour cycle at 80% and my C02 is between 25 and 30ppm. I have been dosing 5ml of TNC complete and about 2ml of Chelated iron daily. I started dosing the iron because many of the plants had yellow leaves with dark veins. I do water changes weekly.
Should I dose more or less or could it be a different problem all together?
Any advice would be greatly appreciated.
Thanks.
 

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Hi All.
This is my first time posting on here and I could really use some help. My tank has only been set up for a few months now as I have had to restart a few times because algae got out of hand. This is the most success I have had since I got into aquascaping about two years ago. Although my plants are now growing and they have a lot of roots I don’t think they are thriving, and the algae will still take over eventually if I don’t do a good scrub regularly.
I can’t help but think it could be better than this. Since I have never experienced a balanced aquarium I don’t know.
As you can see from the photos I am struggling with green spot algae and blackbeard algae is starting to appear in places. The tank is about 100l with a sump so a total volume of 120l of actual water. I have recently added 3 Otto’s and 4 Amano shrimp but have ordered some more. Also have: 7 Rasboras, 4 Corys, 4 Rummynose Tetras and 1 Hongkong plec. My lights are on an 8 hour cycle at 80% and my C02 is between 25 and 30ppm. I have been dosing 5ml of TNC complete and about 2ml of Chelated iron daily. I started dosing the iron because many of the plants had yellow leaves with dark veins. I do water changes weekly.
Should I dose more or less or could it be a different problem all together?
Any advice would be greatly appreciated.
Thanks.

Hi @HBomb 5 ml daily of TNC Complete should be fine as far as I can tell for a 120L tank (the sump counts towards the body of water) - its 35ml per week which is fine if you target EI - keep the high dosing (which is not that high btw. you could even increase it..) - it's not the reason for your algae problem. Your algae problem looks like a classic CO2 application/light intensity and flow issue - a full tank shot would be helpful with more details on how your dosing CO2 ... timing, pH profile, equipment. I am not a CO2 specialist so hopefully others will chime on that or you can dig into the vast amount of CO2 threads with solutions to similar problems. See if you can better your flow throughout the tank.
To get the upper hand on this issue you should increase your weekly water changes / amount and lower your light intensity - the 8 hours is fine, but dial it down to 50% while you're working through this. Also you should start dosing some PO4 on top of what your getting with TNC Complete (such as Sachem Phosphate) to accelerate the decline of the GSA.

Welcome to UKAPS :)

Cheers,
Michael
 
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you are dosing about this daily:

N 0.62500 (2.74 ppm NO3)
P 0.08333
K 2.08333
Mg 0.33333
Fe 0.03333
Mn 0.00750
Cu 0.00083
B 0.00417
Zn 0.00417
Mo 0.00042

I doubt what you are seeing is an Iron deficiency, it very well could be Mn and Mg. but based on those pictures it doesn't appear you have Iron deficiency, I do see varieties of algae growing on the leaves, wood etc. what kind of additional Iron are you using? what exactly are the water parameters?

I would recommend adding additional Mg and Mn and go from there, you can keep your TNC dosing same as it is right now.
 
You could easily double your TNC complete and still not be approaching full EI. As you’re running high tech, I’d suggest increasing your TNC complete to 10ml daily and see how you go. Algae is often caused by nutrient deficiency as they can outcompete plants when there is insufficient nutrition.
 
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I would recommend adding additional Mg and Mn and go from there, you can keep your TNC dosing same as it is right now.
What @Happi said... as it is frequently an issue in the UK that you tap water is very low on Mg... (assuming your using straight Tap and living in Brentwood UK and not US :) ).... I would say 5g of MgSO4 (Epsom Salt) per week which would add 4 ppm of Mg in addition to what your getting from the TNC... and as mentioned, your high dosing is really not that high... so go with @hypnogogia advice as well and double it - that will put at 38 ppm of NO3 weekly instead of 19 ppm.
 
The plants in general look fairly healthy, the only problem I see nutrient wise is possibly a lack of P04, this thread might be of some use phosphate with EI - higher than 3 ppm?

Your algae problem looks like a classic CO2 application/light intensity and flow issue

Very hard to work out how the flow is being circulated from that spray bar but it looks like you have the flow pointing down, you also appear to have very little surface agitation. Maybe this configuration can work, but it seems unusual.

With the types of algae you have lights have to be considered, I'd automatically suggest you reduce the intensity, but will respectfully ask what light illuminates this tank.
 
Thank you all for the advice so far. I’ll start by trying to answer some of the questions asked.
I’m using a pressurised C02 system with an inline defuser. It starts 3 hours before lights come on and turns off 30min before lights turn off. It’s been a while since I checked the BPS because I was going by the drop checker colour and also measuring the KH and PH to work out the C02ppm. Last time I measured the PH was 7 and the KH was 9 degrees which gives me 27ppm. We have fairly hard water in my area so I have to use more C02 hence why I have no surface agitation. Also the water flowing into and through the sump has a lot of agitation so I figured that would be enough. Ammonia 0, Nitrites 0, Nitrates normally around 30ppm but near the end of the week closer to 40ppm, Phosphate between 0.5 and 1ppm at the moment, GH 16 degrees/286.4 ppm. The pump has a flow rate of 2000l/h but I have it running at around half that. I had it running stronger in the past but the plants were swaying about a lot and the fish struggled.
I made the spray bar myself and the nozzles can be adjusted to almost any angle so I have them pointing in different directions to try and hit every spot. In general they are pointing down though.
I agree that there isn’t and iron deficiency at the moment but a few weeks ago almost all the plants had yellow leaves on them with dark veins. That all went away shortly after a started dosing the iron. I am using an EDTA Chelated Iron, 13% which I mixed at a ratio of 20g per 500ml. I have been adding 2ml per day which is about 0.104ppm for my 120l, I think.
I’m using regular tap water and Seachem prime and yes I live in the UK.

The most difficult part to answer is the lights. It is a light that I made myself. I designed it using the Tropica Lumens/litre guide and countless research on what spectrum and Par levels. It consists of the following high spec LEDs ordered from the US:
94 x LUXEON 3535L COOL WHITE 5700K LED
14 x LUXEON 3535L WARM WHITE 2700K LED
12 x LUXEON 3535L BLUE 475NM LED
12 x LUXEON 3535L Red 620nm-630nm LED

Now this probably doesn’t help you in determining if my lights are correct but since I finished this light I have had the best plant growth since I got into this hobby. I have never managed to get the Monte Carlo to grow so well and carpet. It might just be too intense, but that is an easy fix.
I hope I answered all your questions but I you need more info please let me know and I’ll do my best.

Thank you
Hannes
 
Having had Algae infested AR in my tank (usually the lower leaves), I would say that its "excess waste" and "unstable parameters - including unstable CO2". After improving tank cleanliness and CO2 stability, the algae situation on my remaining AR is much improved.

I have AR in my low tech tank - not as red, but no algae - it suggests that what ARs like is to be left alone, with stable parameters... whereas in high tech we tweak things too much. I was tweaking my CO2 recently and algae appear on one of my AR's leaves :cool: To quote 2hr Aquarist on this:

Alternanthera reineckii is not a demanding plant - often it suffers because aquarists try to do too much rather than too little; changing too many variables frequently. Alternanthera reineckii requires a sustained period of stability to do well.
 
Hi @HBomb and welcome to the forum :)

I was going to post a compare sheet of TNC v EI dosing with a full breakdown of what your dosing and what may be missing, that would just make it look to technical and boring.

With a 100Litre tank IMO it is worth making your own ferts, so getting some salts and moving to full EI dosing will be cheaper than buying TNC or any other ferts and your plants will love you for it.

Although my plants are now growing and they have a lot of roots I don’t think they are thriving, and the algae will still take over eventually if I don’t do a good scrub regularly.
I can’t help but think it could be better than this. Since I have never experienced a balanced aquarium I don’t know.
As you can see from the photos I am struggling with green spot algae and blackbeard algae is starting to appear in places.
I have never managed to get the Monte Carlo to grow so well and carpet.

Which is all pointing to fluctuating CO2 levels and/or Tank turnover/flow, which is the number one cause of issues in a CO2 injected tank. Plus too much light for present Fluctuating CO2 levels. I have grown Monte Carlo (MC) with 50cm of water and low light in that area, however flow was excellent and CO2 was stable from lights on till CO2 off. I class stable CO2 a pH drift less than 0.1pH from lights on till CO2 off - which is tricky to achieve

We could do with some details of filter output, plus have you done a pH profile from CO2 on till CO2 off - this will highlight fluctuating CO2 levels

I would reduce photo period to 6 hours and reduce light intensity whilst the CO2 and Flow are addressed
 
@HBomb
"I have been adding 2ml per day which is about 0.104ppm for my 120l"

0.7 ppm Fe weekly is quite a rich dose. I suggest using DTPA Fe rather than using EDTA and dose about 0.15-0.3 ppm Fe weekly, TNC already use EDTA based Iron, using DTPA would be more beneficial in case of harder water. as mentioned earlier, I would try to add some extra Magnesium and see what happens. also if you could get some MnSO4.H2O and dose about 0.075-0.15 ppm weekly you should see some kind of response.

weekly Dose:
current dose of TNC
about 5-8 ppm Magnesium to changed water
0.2 ppm Fe DTPA (not EDTA)
0.1 ppm Mn
 
Hi Zeus.
What do you mean by filter output? I have a sump filter which I thought is more than big enough as it holds about 20-25l and can easily handle a flow rate of 2000l/h. It has large mechanical filtration and more than enough biomedia. I was under the impression that you should aim for a flow rate of 10x the volume of tank water. So for the 100l only that’s a flow rate of 1000l/h. If you include the sump I should be aiming for about 1200-1250l/h. I have increased the flow slightly since I started this post.

How do I do an HP profile? How often should I take a reading throughout the day? I can do it tomorrow and post it here for you.

I have seen an EI kit on ebay that someone does which has everything you need plus instructions to make your own EI fertiliser. Will this work?

Thanks
Hannes
 
Here are screenshots of what’s in that kit.
 

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I have a sump filter which I thought is more than big enough as it holds about 20-25l and can easily handle a flow rate of 2000l/h
So filter/pump output is great :thumbup:- next would be what output method are you using? lily pipes/spray bar. If its just a pipe with a wide bore then it will generate little flow in tank. The should be surface movement/ surface agitation and the plants should sway with the CO2 bubbles being force all the way down to the substrate level, ideally with flow at substrate level as well;)
If your not doing a carpet flow at substrate level isn't as critical

How do I do an HP profile?

take a glass of tank water and let it degas 24hrs and take pH or place it in a bottle half fill it and shake it lots releasing air every so often till there's no pH change. that pH is the degased pH of tank. lets say its 6.5pH ( doesn't matter what it is, the degassed pH is what you use).
Your aiming for 30ppm CO2 so that's approx. 1.0pH drop so target pH in this example is '5.5pH'
start taking pH at CO2 on and every 30 mins till CO2 off and at lights on.
at lights on it should be 5.5pH (if degased tanks water pH is 6.5)
Then 'ideally' the pH from lights on should remain at 5.5pH till CO2 off, less drift the better - I aim for less than 0.1pH drift

Getting a stable pH/[CO2] is hard
get it stable with good flow is the first step by adjusting injection rate/BPS. then do not adjust injection rate/BPS again. then you just time how long it takes to reach target pH- if its 2hrs or 4hrs you accept it, as with single injection CO2 methods your pre CO2 injection time is what it is. Only with expensive twin injection can you speed it up and it can be fatal to all your livestock very easy if its done wrong.
 
Hi Zues.
I am using a spraybar with nozzles that can adjust to different directions. They definitely create a lot of flow and I have some of them pointing down/angled etc. You should be able to see that on the photos I have attached. I have also taken some photos at substrate level to show how many bubbles there are lower down and even all the way at the other side of the aquarium at that level. The plants are swaying but not too much. Unfortunately I can’t post a video of that.
I will do a PH profile tomorrow every half hour and post the results tomorrow evening.
Thanks again everyones advice so far.
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Flow from pics doesn't look bad as it has the '7up' appearance. Spray bars are IMO the best way to generate form from a filter/pump. They normally work best along the back of the tank with the jets aims to hit the front glass. This creates good surface agitation and all the detritus will gather at front of tank for easy spotting/removal as when the water hits the front glass it is forced down to the lowest part of substrate then flows along bottom of tank to the back of tank then up the back to the spray bar again.

I don't like the '7up' appearance which is why I took the CO2 reactor route so tank is 'Gin' clear except for pearling. Maybe something for the future

Your CO2 profile may be fine, unlikely as very few get it right first time. Well worth checking then we can think other ferts as CO2 is the main fert in a high tech tank

Your algae issues may be just too much/intense light, which is very easy to do with modern LED lights, most of us in the hobby have melted many of our plants with too much/intense light, I have and they pearled like mad then melted
 
Here are screenshots of what’s in that kit.
Looks the same as the APFUK starter kit from your pics which normally cost about £20. It will contain everting you need to start DIY ferts and easy to move on to EI dosing as well
 
Zeus
I forgot to ask, how much surface agitation do I need? Someone said that because I am using a sump filter that is more open than a canister filter I should be getting enough agitation as the water flows through it and back into the tank. Because my water is so hard I use a lot more C02 as it is and any surface agitation in the tank will increase my C02 demands even more.
 
Zeus
I don’t like the ‘7up’ look either but I have to live with it a little longer. I am currently designing a new type of reactor which if my calculations are correct should be more effective than current designs on the market. I hate wasting C02.

I can change the orientation of the spraybar to face the front glass and see what effect that has. I might do that in the new year.
 
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