Planted Tank Not Thriving

Lmuhlen

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Jan 20, 2021
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Brazil
Hello all.

I'll try to make this as thorough as I can, but in any case my issue is that plants don't go as well as I wanted them to, the leaves on larger plants seem to age fast, smaller plants wither and die, slow plants get fuzzy algae on their edges... I tried so many things already, but nothing really helped in a noticeable way. So I would like some help pinpointing where the largest fault lies.

Tank info:
It's been running for around 9 months already, with no lack of maintenance.
330L - 1,3x0,5x0,5m

Illumination: 2x Finnex ALC-24

Filter: Oase Biomaster 350 canister 1100L/h. Input with surface skimmer, output is a lily pipe.

Substrate: DIY substrate with an earthworm humus layer (~2cm layer) covered with fine gravel (1~2mm)

CO2: Cylinder, using inline diffuser at the canister's output. A dropcheck is usually around light green~yellow, indicating a high CO2 concentration.

Fertilization: DIY powder mix with KNO3, KH2PO4, KCl, MgSO4, adding 20ppm K, 7ppm NO3, 3ppm PO4 and 0,5 °GH Mg weekly, divided into 3 doses. I also dose a micros liquid fert that emulates CSM+B, roughly 0,23ppm Fe weekly, dosed everyday. I complement with 0,4ppm FE gluconate weekly, in 3 doses.

Water changes: 30%+ weekly. I add CaSO4 and MgSO4 to raise the GH from 3 to ~7.

Water parameters that I can measure:
pH ranges from 7,2 to 6,2, due to the CO2 injection; KH between 0,5 and 1. GH around 7; NO3 roughly 20ppm; PO4 roughly 2~3ppm. That's the NO3 and PO4 measurements just before water changes.

I have 2 4500L/h wavemakers helping with water flow, one boosting the output of the filter to add range to the CO2 mist, the other one complementing the other side of the aquarium. Both are positioned near the water surface, tilted slightly down so that the water reaches the bottom of the tank, to help with O2 diffusion.

Plants that grow OK: Echinodorus small bear, red nymphaea, different cryptocorynes, microsorum narrow leaf and windelov, Echinodorus parviflorus, blyxa japonica, unknown moss, H. corymbosa compact. Even though they are surviving and growing, they seem to age fast, the older leaves get some fuzzy algae and I have to trim them frequently to remove these leaves. The corymbosa are constantly losing old leaves, filled with holes, and some traitor is taking a bite at the new leaves, but I think that could be a sign that they are weak.

Plants that wither and die: pinnatifida, staurogyne, P. helferi, lilaeopsis novaezealandiae, Marsilea hirsuta, A. reineckii mini, hydrocotile tripartita mini, monte carlo (this one is surviving, barely), and maybe others that I won't remember.

Anubias nana and coffefolia, and bolbitis are now growing well, but in complete shade, receiving zero direct light. When they were exposed to the light, they would grow fast, but were overcome with all kinds of algae. Still to this day, if one of the leaves of the bolbitis escapes the shade and touches the light, it gets infested with algae, it's like a vampire...

Over these months, I have tried a bit of everything, fine tuning the dosages, adding and moving around the circulation pumps, adding media in the cannister, raising CO2 to the point of seeing the fish gasping...

My 2 biggest suspicions are lighting and substrate. For the substrate, unfortunately I can't do much about it right now, but I do add osmocote every now and then, and the plants seem to react well to it. The humus forms a lot of gas, but I'm pretty sure it's CO2 since it doesn't smell and isn't flammable. At the start, I thought that maybe the humus was too strong for the more delicate, smaller plants, but it is a relatively thin layer and today I think that maybe it is not enough... And then there is the pinnatiffida that I planted on the hardscape and it still withered just like the others.

For the light, I can't really tell if it's too strong or too weak. Most of the plants that died wouldn't mind some stronger lighting, I suppose, and I don't think they would wither because it is too strong. But at the same time, the slower plants suffer visibly due to the excess light. I tried a bit of everything with the light, right now I'm trying to reduce it, I raised it a few centimeters, as much as I could fir inside the lid, and I reduced power the plateau from 100% to roughly 80%. I haven't really noticed any difference.

As for the photoperiod, these lamps allow for settings every 3 hours, so there isn't much flexibility... I tried a 3hrs plateau, that corresponds to 6hrs at 50%+ power, due to ramp up and down, and now it is at 6hr plateau, which adds up to 9hrs with the ramps. In every case, I leave what I consider to be very weak light for 6 more hours after the plateau, for viewing purposes. I still keep the CO2 pumping during that time, just in case. These power percentages are very dubious, they are a setting that doesn't necessarily translate directly to actual light power. The view time is mostly RGB light, under 40% power, without the white LEDs.

Other than the fuzzy algae on leaves and some BBA on the hardscape, which is slowly reducing, right now I don't have many algae issues, but during the first months it was a war.

Right now I'm trying a few less demanding plants, to see what happens.

Whats-App-Image-2021-04-30-at-10-23-31.jpg

Whats-App-Image-2021-04-30-at-10-23-30.jpg


Any input will be greatly appreciated.
 

Mooner

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Lmuhlen,

Consider these points:

1. Surface movement, aim the wave makers parallel to the water surface creating surface agitation and circular motion across the top of the tank, then returning flow along the substrate. Your flow setup is a challenge because moving water from side to side rather than front to back of the tank requires a lot of force(water movement). You want the plants opposite the pumps(far side of tank) to sway slightly. If you get this flow right, you will use a lot more CO2, yet the fish will not gasp.

2.Use https://rotalabutterfly.com/nutrient-calculator.php at your 330L tank size for dosing EI. Weekly CASO4, MGSO4 should be adequate at your 50% WC schedule. KNO3, KH2PO, KCI or(K2S04), CSM+B per EI schedule(every other day Macs/Mics). IMO and IME, forget about the testing NO3,PO4, just use the calculator and concentrate on the CO2 + water flow. GH around 5, KH2-3.

3. What is your filter maintenance? Since the CO2 is reliant on the filter for flow, this filter maintenance should be done weekly with the WC. At least the pre filter on the Oase? Not sure, I use Eheim classics.

4. Running two 2x finnex(this is a lot of light), set the lighting at 6-7Hrs photo period at about 40-50% (slowly moving up, this will require adjusting CO2 as you go) Use all RGBW spectrum's. IME, the red and blue do not cause algae issues. That being said, consider using just one lighting fixture at 75%ish until you get a handle on CO2/Lighting/water flow. Lighting/Ferts variables need to be set as to concentrate on CO2 and flow.

5. After getting #1 right and before this step, start the CO2 1-2 hours before lights on on to ensure the CO2 concentration is adequate. How are you measuring the Ph Drop?

6, I wouldn't be concerned with the substrate type or the Osmocote at this time. The EI water column dosing will work fine. Especially with the lower tech plants.

Concentrate on the CO2 an the water flow around the tank(the biggest challenge with your setup). The more intense the light, the more CO2+water flow you will need. EI ferts are set them and forget about it.

Overall, the tank looks good!

My two cents, Good luck.
 

Pauld738

Member
Feb 24, 2019
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Modesto, CA
I second what has already been said but I would like to throw out a few things that caught me eye.

First is your water change schedule. You are dosing essentally EI dosing yet you are doing only 30% water changes? Is that right?

If so, not nearly enough. For EI dosing. Myself as well as most if not all the aquascapers I follow online will do 70-80% water changes, sometimes a few days apart, to handle aglae issue. Not saying you have to go to that level but if you are indeed only doing 30% water changes you are on the other end of the spectrum.

Second, that is a pretty deep tank? 121cm length or there abouts? That should put you at roughly 61cm height? That's a tad deep for a 24" Finnex? Maybe? I know Finnex likes to market their par at 50/18" but most manufacturers like to fluff their data for sales. Plus based off their website those reading are thru open air. Not water. If so... huge, huge difference over the coarse of 50cm or so of water.

It also appears that the tank is next to a sliding glass door. So lots of ambient light. My co2 tank is also in a very well light room (my kitchen) and for 3 months out of the year gets direct sunlight from a sky light for about an hour. I don't reduce intensity to deal with this but rather reduce duration and have no lights on during midday (or morning for that matter). That helped tremendously deal with the algae issues I was dealing with. I ran with only 3hrs at 100% intensity, 4hrs <50% split ramping up and down for almost a year (since I get no algae on the glass by water change day I am slowly bumping that up). I didn't quite understand your photoperiod but it looks like you are running lights at it's highest midday (ish), which would be the worst thing to do. If you need lights on for viewing in the morning, ideally you should have them off during midday (siesta) when ambient light is at it's highest. Then back on in the evening. But this is the problem with those Finnex lights. They like to let you think that you have control but you really don't, lol! :)

One thing to consider would be to re-arrange plants in the tank into zones. One end for plants that are doing well now, with lighting levels that are working for you know. And the other end with lights full blast (perhaps with a different spot light that can penetrate depth?). For carpeting plants at the substrate. You would have to abandon the 2 hills with a valley approach that it looks like your were trying to go for and opt for more of a triangle look to the tank. Low on one end rising the surface on the other. And this assumes that root growth now looks good. Everything nice and white.

Lastly, and this depends on what algae was growing (I know you said beard and fuzz now) on your Anubias and Bolbitus, perhaps experiment with bumping up your phosphate. I follow tanks that run at 6ppm, sometimes higher, without issue.

All that said the tank is enjoyable to look at. :)

Good luck!
 

easternlethal

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Plants which don't do well in the short run are typically due to co2 so you should direct co2 towards it either by redirecting flow or moving them all to one corner and placing a co2 diffuser near it. Put a drop checker nearby also to make sure. Then bury a capsule of osmocote nearby (not directly underneath).

It always helps to find some information about where the plant is from in order to understand its lighting and temperature requirements.

For example hygrofilia pinnatifada is from western ghast in India which means it should be most comfortable between 20 - 25 celcius and be able to handle high lighting.

Understanding plants and how co2 is distributed within the aquarium is key imo.

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Lmuhlen

Member
Jan 20, 2021
53
14
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Brazil
Thank you all for your inputs and suggestions!

For rooted plants, check their root whether they're healthy or not.

I just pulled a couple of plants which have been basically dormant for months, neither thriving nor dying, and their roots seemed fine. White, long... Are there any particular signs to look for? I also dig up a few plants from time to time, such as the blyxa and the corymbosa, for trimming purposes and nothing seems wrong to me.

Lmuhlen,

Consider these points:

Point 1, water flow - This is indeed a point which I've been trying to work on for a while, at first I only used the filter for circulation, but that just wasn't enough for the full length of the tank. Now with the 2 extra pumps, I've been trying to experiment different setups. What worries me about having a strong flow from one side to the other with my setup, that has all the equipment cramped on the wall side, is that it makes the surface skimmer useless if everything gets pushed to the other side of the tank. But I just tried something new to improve flow near the surface. Now one of the pumps is boosting the filter outlet to help the CO2 reach farther, aiming from top to bottom with a gentle slope, and the second one is parallel to the surface, in a way to make a circular current on the surface, still keeping the skimmer on the end of the loop. The surface looks really wavy now, I'm sure it is oxigenating well. I can follow CO2 bubbles traveling through the entire length of the tank, near the substrate, and return from the other side up to the middle of the tank, where it gets chaotic.

Point 2, EI dosing - I didn't plan on going EI, I've always kept it leaner. I compared my dosing with the calculator and I'm doing roughly half of what it suggests for EI. Only potassium seems to be a little higher than half, while nitrates are a little lower. That is also why my WCs are only 30%. Do you think I could be having issues due to a too lean dosing schedule? How important is KH? I'm having trouble raising that one, I didn't want to add baking soda, but I couldn't find any replacements either, potassium bicarbonate is a controlled substance here... I recently bought some calcium carbonate, but I haven't tried it yet. So hard to dissolve...

Point 3, filter maintenance - I do clean the pre-filter weekly, sometimes even sooner than that. The skimmer and the lily pipe really help to identify when the flow rate drops, and it happens suddenly. At some point it is fine, than the last part of the pre-filter gets clogged and the flow rate drops to a fraction. But the pre-filter is a little too effective and I have to open the filter itself very sparsely. It seems to never get clogged.

Point 4, finnex light - I have 2 lamps because I couldn't ship the 48" one, it is too large for long distance shipping, so I'm using 2x 24". They are not side by side, they are placed one after the other. That makes it basically the same as a 48" long, which would be the correct size for the tank, with just one less cluster of LEDs.

Point 5, measuring pH drop - I collect water with a syringe from the middle of the tank. When I measure for the no-CO2 value I use the syringe to blow air through the sample for a minute or so, to vent the remaining CO2 away. It has been a while since I've done this procedure, but at some point I was keeping a close track to it and still couldn't improve the situation. I recently bought the drop-check, and been trying to use it as a rough guideline. My pH test isn't very easy to read past the 0.2 resolution and is also limited to 6.0.

I second what has already been said but I would like to throw out a few things that caught me eye.

As I answered to Mooner, I'm not dosing EI, it appears to be closer to half EI.

The tank is 1,3 x 0,5 x 0,5m. The water column is ~43cm. I did find it weird that they would announce their PAR readings through air, thought that maybe it was a mistake...

The room is indeed well lit during the day, but the tank gets no direct sunlight. Originally I wanted to shift the photoperiod to start later during the day, to enjoy it after work, but I chose to keep the photoperiod similar to the natural light to avoid having a lot of natural light during dark hours. That is also why I expanded the photoperiod with a lower intensity light setting, so that I can enjoy the tank at night, when I get back home.

The light setting is as follows:
7:30 to 10:30am, ramp up from zero to full (80% setting). From 10:30 to 4:30pm, plateau at 80%. From 4:30 to 7:30pm, ramp down to 30% RGB and 0 white. From 7:30pm to 10:30, ramp down to zero.

As you well noted, Finnex aren't as flexible as one would think they are... The 3 hour resolution is rough. Do you think the low-light setting for the late afternoon period could be an issue? What about the plateau setting, should I go higher, lower...? I'm really lost at this point.

As for your suggestion for a layout change, right now I'm trying to get this to work. But if I give up or feel like changing it, I will consider doing a triangle with different light settings for each zone. I just feel like maybe there is something important I'm missing and I don't want to plan a new setup and risk repeating it. The layout right now looks a little messy, but it is mostly because most plants didn't make it, so I had to improvise a lot.

As for the phosphate suggestion, I'll increase it 50% on my next mix, assuming I don't just go EI after the suggestions I get here.


Understanding plants and how co2 is distributed within the aquarium is key imo.

Thanks for your input as well. Over the course of these 9 months, I tried a few different ways to distribute CO2, and I'm still working on that, I also think it is important to get it right. But right now it seems that plant growth is bad everywhere. When I gave up sticking to the layout, I tried placing plants of the same kind all around the tank, and they all reacted the same... The pinnatiffida was one of those, I put some samples near the substrate, near the light, near the filter outlet, on the opposite side... they all died.

As for temperature, I have it set so it can fluctuate from 25°C to 27°C. The heater keeps it from going lower and I have a fan that tries to keep it from going higher. But I don't really trust any of the thermometers, I just chose one to follow so that I don't go insane, but I wouldn't be surprised if it was a whole degree wrong.
 

easternlethal

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If plant growth is not good overall then it's probably co2. Are you getting any pearling? A lily pipe actually restricts flow so you might try without it.

My tank which is about 400 litres uses just one pump which sprays from left to right along the back. I did use wavemakers but they just looked too ugly. So I used 8 dropcheckers (four on each side) and increased my injection rate and have it come on 3hrs before lights on.

I think your photoperiod may be a little high as it sounds like you have lights from 7:30 until 10:30pm. I would dial it down to just 5 or 6hrs a day in a stretch.

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Pauld738

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Honestly I don't think you have nearly enough light intensity. But it can be very difficult to diagnose over the internet so we are all just guessing in the end, lol! :)

Those 24" Finnex are not the same power as the 48". About half actually. And with roots being healthy it points to me that you don't have enough light at the substrate.

But don't confuse intensity with duration. Your ambient light might actually be pretty big even though no direct sunlight. You can actual get an idea of how much with a phone app called Lux. It's not something you would want to use for critical missions but it would definitely give you an idea of how much extra light you are getting at the front glass of the tank. I just tested this afternoon on mine. No direct sunlight yet, that comes later in June, but I'm at 330 lux.

I would consider your dosing EI (it's a range not an exact number), even though your nitrates are low (mine are too) and my main concern would be the accumulation of micros with only a 30% water change. Macros are just that, macro. They can go quite high without too much worry. Of course there is always a ceiling. Plus the removal of dissolved organics is always warranted. Not sure you get enough of that with only a 30% water change.

Lastly don't mess with kh, just make sure it is steady. That is definitely not your problem. Way too many successful 0 to low kh, and the resulting pH, aquascapes out there for that to ever be the issue. And this is in relation to plants. Now if you want to cater to a certain species of fish that is another thing. :)

**Edit**
Just wanted to clarify my kh comment...

Adjust kh to whatever feels comfortable. You just don't need to adjust it. :)

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Last edited:

kizwan

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Thank you all for your inputs and suggestions!
I just pulled a couple of plants which have been basically dormant for months, neither thriving nor dying, and their roots seemed fine. White, long... Are there any particular signs to look for? I also dig up a few plants from time to time, such as the blyxa and the corymbosa, for trimming purposes and nothing seems wrong to me.
That's healthy root. Healthy root helps substrate oxygenated & this helps beneficial bacteria in the substrate thriving. You can safely rule out substrate.

My suspect would be CO2 as well. Try move the drop checker to the area where the plants are not doing well.
 

Lmuhlen

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Jan 20, 2021
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Honestly I don't think you have nearly enough light intensity. But it can be very difficult to diagnose over the internet so we are all just guessing in the end, lol! :)

Those 24" Finnex are not the same power as the 48". About half actually. And with roots being healthy it points to me that you don't have enough light at the substrate.

Thanks again for your reply. I'm using two lamps with 24", to make it close to what a 48" would do. In the end, each half of the tank is powered by a 24" lamp.

I'm having this problem where I don't know if my issue is too much light or not enough light, or maybe neither. It is hard for me to know, not really having the experience with the different plant species to understand their reaction. As an example, I read that Ranunculus papulentus would grow tall in low light, or near the substrate with high light. So I bought some and placed it in the center of the tank, where there is great flow, no shades, nothing to get in the way, to try and have an indication of how much light I have. They just died after a few weeks, without growing a bit. Then there is the issue with the slow growers such as bolbitis, which seem to hate the direct light in my tank, indicating that maybe it is too much...

Based on all the feedback, what I will do is try to squeeze more CO2 into the tank now that the water is flowing all around, swaying all leaves, then increase WCs a bit, up to 50% and set lights back to 100% power at the plateau.

Another question that came to me is regarding the extended perioed of time in which the tank is exposed to low light, for viewing purposes. Is it possible that it is hurting the plants? I would expect plants in nature to have strong direct light for a few hours, and then only indirect lights for the rest of the day, but aquariums and nature don't seem to meet eye to eye... maybe the strong light for half the day is hurting the slow growers, while the weak light for the other half is hurting the fast growers, and everyone is unhappy? There is one thing I haven't really changed during these 9 months was this setting with ~6h of reduced light.

If plant growth is not good overall then it's probably co2. Are you getting any pearling? A lily pipe actually restricts flow so you might try without it.

I ocasionally get pearling on the microsorums and the nymphaea, but that's it. But ever since I boosted the circulation with new pumps, it stopped. Not enough localized O2 saturation, I'm guessing.
 

easternlethal

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Well lights and co2 are always related because you can have more co2 and lighting than another tank but plants still die because there is too much in relation to the co2 being supplied. This is why instead of increasing co2 it's sometimes easier to just lower or shorten lighting periods and study the effects. And as lighting intensity is concerned I agree that high levels for shorter periods is better than low levels for longer periods. Low light plants (even buces and crypts) can absolutely handle high levels.

Hard to see how the flow is working in your tank but too much of it with surface agitation just causes co2 to escape imo. If you imagine that your tank was filled with carbonated soda water and you add 2 wavemakers to it, fizz will escape a lot more quickly than if it were completely still. Thats why I usually try to tune co2 by playing with injection to rates and on off periods instead of flow.
 

Pauld738

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Feb 24, 2019
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Thanks again for your reply. I'm using two lamps with 24", to make it close to what a 48" would do. In the end, each half of the tank is powered by a 24" lamp.
That's what I was trying to get at. :) I could be wrong but I don't think that 2 24" get close to what 1 48" can do. Power wise. And you have some depth to deal with in your tank. I do understand that you are seeing contradictory plant growth (bolbitus and the rp) so that may, or may not be it. As is with most cases, there is probably more than one thing going on in the tank.

As to low light over extended periods, imo & ime that would not hinder plant growth. Help algae grow yes, lol! If the tank balance is off, like it can be in the beginning. But the key would be to have a period of time, like in nature, where there is adequate intensity for all plants to grow. Of course an Anubia has drastically different requirements than a fast growing stem. And within that, Hygrophilia poly has different requirements than, say, alternanthera reneckii. So it can be difficult to cater to all.

There was one thing that struck me this morning while looking at my tank pictured below. I remember you said you had tried hydrocotyle t. And like others had just wasted away. I'm wondering what would happen if you just floated some in your tank? I regularly float hydrocotyle and other stems in my tank(s). The idea would be that if it still wastes away then there is an issue with your water. If it does great, try planting in substrate. If it wastes away after planting, then it might point to a lack of light? I know when I move cuttings to my other tanks I have to be careful about where to place it as I have had die back/off when planted at substrate level with lower light.

The hydrocotyle in the pic is trimmed in half about every 2 weeks or so and is there to keep fish from going in the overflow as well as allow my ramshorns to pull themselfs out when they get stuck in there. The Rotala, lower left corner, was a bunch that didn't want to stay rooted after a trimming and I just left it there because my Phoenix rasbaoras seem to like it as they hang out in that corner now when they used to not. Fyi, pic was taken at 10am and tank lights are off so you can get an idea of what kind of ambient light I get on this tank during the day. My lights start ramping up around 1:30pm, full intensity hits at 3pm. I'll probably back this down to a 3pm start here by the end of the month as direct sunlight will start to hit the tank for about an hour a day around the 2pm time frame.

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Lmuhlen

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Jan 20, 2021
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It's been a while since I did some changes to the tank, following the suggestions provided. So far, it seems like I had some improvement, but it is still far from what I expected from this setup. I greatly improved surface aggitation and I think that was very positive. I now have a more stable concentration of CO2, at a higher level as well, without any indication of disconfort from the fauna. At the time, I didn't change the light all that much, I just gave up on the extra time with low intensity for viewing purposes. Now the lights ramp from zero to full and from full to zero. I also added some quick and easy plants to make some plant volume. They didn't grow as lush as I expected, but they are alive and growing.

The biggest difference I found in plant development was with the nymphaea, which is the plant I thought was doing better. Its leaves would grow very fast and very large, going from newborn to the point where they started reaching the surface in about 3 weeks. It was kind of annoying, I would have to trim them very often, and at any given time I only had a few very large leaves. After the changes, the leaves are slightly smaller but the thing is that they don't grow so tall, I don't have to trim them anymore until they age and start showing signs of decay. That made the plant look better, overall. I think there really was some gas exchange defficiency and the plant was trying to reach the surface. Recently I moved it to a corner, next to the largest wood piece, in order to get a wider middle zone with direct light, to try and grow some plants there without worrying about shading.

I also found out that some fish is eating my plants, most likely an angelfish... Not sure what to do, probably just make the plants grows faster than they are eaten. This may be one big reason why some plants seemingly disapeared...

After meditating a little on the issue of having too much or too little light, and after reviewing the PAR values provided by the supplier and reading about how air readings compare to readings in aquariums, I decided to test if the light was too strong, instead of too weak. I mostly reduced the white LEDs intensity, keeping the RGB at middle/high values, with the red lights on max. It's been only a week, so no results to report yet, other than the new spectrum being more pleasent to look at, looks a little warmer.
That's what I was trying to get at. :) I could be wrong but I don't think that 2 24" get close to what 1 48" can do. Power wise. And you have some depth to deal with in your tank. I do understand that you are seeing contradictory plant growth (bolbitus and the rp) so that may, or may not be it. As is with most cases, there is probably more than one thing going on in the tank.
Looking at the info provided by Finnex, it does look to me as if 2 24" are very close to 1 48". The 48" has twice the number of LED clusters +1, and the total power of the lamps seem to agree with that, so the LED clusters are probably the same in both models. In any case, I'm now working under the assumption that less light will help me... if it proves to be false, then back to more light and possibly a different lamp.

As for letting plants float, I didn't try that, but I have some plants really close to the surface and they don't look much improved compared to their equals near the bottom. I did notice, however, that the newly added zosterifolia looks better when they reach a height of ~10cm, but since they are kinda new, it may be a matter of adaptation and with some prunning they will look good from bottom to top.