Amazon Swords little growth after 1.5 months and algae growing on all leaves

[codr72]

Hello,

I planted some amazon swords across the back of my tank about 1 and a half months ago now and supplemented them with seachem root tabs next to their roots. My only issue is they seem to be growing very little and every leaf on each plant has some form of fuzzy algae growth. Since I have supplied them with root tabs I am leaning towards thinking this is a lighting problem? My tank is a 54l and it came with a 10w white led tube in the lid. I've done some research and found out these aren't great for growing really any plant as it gives me a watts-per-gallon of 0.7. Would anyone be able to confirm if this is likely the problem?

If it is likely the problem then I found a light on amazon which is apparently for planted tanks. But it is an 8w, so it would lower my watts per gallon further, but on the page it says it is suitable for aquariums 60-80l..? Is there more to lighting than just the watts? As it is a mixture of blue and red and white leds (https://www.amazon.co.uk/dp/B08PBHP5PB/?tag=). If it is a lighting problem (I do notice my tank looks pretty dim during the daytime) should I run them both at the same time or just swap out for that one, or should I get the lower wattage one?

I'll attach a picture of my swords here:

Thanks for the help,

Conor

 

[Byron]

The fuzz is black brush algae. This can be controlled through the balance of light and nutrients.

First on the light. Watts per gallon is useless these days as any indication of intensity, except when one is comparing different wattages of the exact same bulb/tube. LED lighting units generally produce more light for less energy (watts is the measure of energy used, nothing else). TYhe spectrum is also important, this is the colour wavelengths used to create the white light. Can you find this data on the unit, the package, or the manufacturer's web site? A Kelvin rating (number with a K suffix) or the CRI (colour rendering index) will tell us. Duration also factors in; if the intensity is sufficient, and the spectrum is adequate, the length of time the light is on can be used to control problem algae.

Nutrients are probably OK here, as I have grown sword plants for years with Flourish Tabs. A liquid fertilizer might be advantageous or not--are you using any liquid now?

A photo of the entire tank will tell us more. The light data we need is the spectrum, and the daily duration.

 

[codr72]

The fuzz is black brush algae. This can be controlled through the balance of light and nutrients.

First on the light. Watts per gallon is useless these days as any indication of intensity, except when one is comparing different wattages of the exact same bulb/tube. LED lighting units generally produce more light for less energy (watts is the measure of energy used, nothing else). TYhe spectrum is also important, this is the colour wavelengths used to create the white light. Can you find this data on the unit, the package, or the manufacturer's web site? A Kelvin rating (number with a K suffix) or the CRI (colour rendering index) will tell us. Duration also factors in; if the intensity is sufficient, and the spectrum is adequate, the length of time the light is on can be used to control problem algae.

Nutrients are probably OK here, as I have grown sword plants for years with Flourish Tabs. A liquid fertilizer might be advantageous or not--are you using any liquid now?

A photo of the entire tank will tell us more. The light data we need is the spectrum, and the daily duration.

Hey mate, thanks for your response. I did some research and all I can find out is that it is a tetra al 10w light, theres no information available on kelvin and lumens on it from what I can see.

We do have a bit of an algae problem though, which is one reason I bought the swords and also cut down lighting, now only on from around 12pm to 10pm. I'll attach a picture of my tank below, please do excuse the current overstocking, trying to convert my tank into platy only and rehome the danios and the platys have produced a lot of fry..

Thanks again.

 

[Byron]

At this point, and because it is the easiest thing to adjust, I would reduce your lighting period. Ten hours is a lot; my tanks are on 7 hours and this problem algae3 has not been in them for six years now (was previously an issue). The hue is red/yellow, which is good (if it is true) as so many LED lighting units are high in the blue which can promote algae. I would reduce the photoperiod to 8 hours, maybe even 7. Use a timer, so it is consistent each day, this also helps plus it is better for the fish.

You didn't nswer my question about liquid fertilizer, are you using any, and if yes, which?

 

[codr72]

At this point, and because it is the easiest thing to adjust, I would reduce your lighting period. Ten hours is a lot; my tanks are on 7 hours and this problem algae3 has not been in them for six years now (was previously an issue). The hue is red/yellow, which is good (if it is true) as so many LED lighting units are high in the blue which can promote algae. I would reduce the photoperiod to 8 hours, maybe even 7. Use a timer, so it is consistent each day, this also helps plus it is better for the fish.

You didn't nswer my question about liquid fertilizer, are you using any, and if yes, which?

So you believe my light isn't the issue? I am not using any liquid fertiliser as I read they are purely root feeders and using it would give them no benefit.

Cheers.

 

[Byron]

I am not using any liquid fertiliser as I read they are purely root feeders and using it would give them no benefit.

This is not strictly true. Aquatic plants assimilate some nutrients via the roots and others via the leaves. It is certainly possible to have healthy sword plants with just the Flourish Tabs, I did it for several years. I now use liquid as well, not for the swords so much as for the other plants especially floating and those not planted in the substrate that would therefore get no benefit from tabs. Any fertilizer in the water will get drawn into the plants via roots and leaves no matter what, but the tabs do concentrate more nutrients in the area of the roots which does improve things.

I was asking more from the perspective of the algae...if liquid fertilizers are being added beyond the needs of the plants, they feed algae. Light and nutrients are involved.

So you believe my light isn't the issue?

I don't know. I do know that 10 hours of light with no liquid fertilizer is almost guaranteed to cause algae. Reducing the duration may be all you need. Give it a few weeks; don't expect the algae that is now present to go away, it won't--the aim is to prevent it from increasing. And this involves the light and nutrient availability. If the intensity is too high, or if the spectrum is not adequate, the duration may or may not make much difference. But it is easy to see, and saves the cost of new lighting if the light itself is adequate.