Who Gives A Fish Forums

Summer's here again and I'm dealing with the same issue - my Amazon sword is melting from the crown. I lost one last year due to this. Every single leaf just rots from the base. In contrast, it grows super fast and healthy during winter.

I think there could be a temperature difference in the aquarium during the seasons. If not, I'd look into the water source - are you using tap water? Water parameters tend to change with the seasons, that might be the culprit.

I've had Amazon Swords outdoors in scorching 40C water and they've been fine, so temperature shouldn't be the issue unless it's a drastic change overnight, which would likely be catastrophic for the fish as well. A change in water supply from your water company, as MrGuppy mentioned, is a possibility - perhaps they alter the source or add something extra during the warmer months. It might be worth contacting the water company to see if they switch sources or add anything during the summer.

I've noticed my swords thrive with extra nutrients. They seem to need a lot of food to stay healthy. I've found that adding a couple of root tabs to each plant every 3 months makes a big difference.

I wholeheartedly agree with the points raised by MrGuppy, coltin, and Snout. In my opinion, it's essential to take a step back and assess the situation by making a list of potential changes that could be contributing to the issue with your Amazon Sword. This list should encompass various factors, including the bioload, lighting setup, nutrient regimen, and water source.

It's also crucial to consider even the smallest details that might seem insignificant at first glance, such as changes in ambient lighting due to window shades or curtains being adjusted to regulate room temperature. Furthermore, massive water changes, particularly those done in rapid succession to stimulate spawning, can have a profound impact on the plant if nutrients are not adequately replenished.

By documenting these changes, you'll be able to identify patterns and pinpoint the root cause of the problem, thereby preventing any potential whipsawing. This methodical approach will enable you to make informed decisions and implement targeted solutions to address the issue at hand.

MrGuppy wrote: ↑Wed Feb 19, 2025 4:26 pm I think there could be a temperature difference in the aquarium during the seasons. If not, I'd look into the water source - are you using tap water? Water parameters tend to change with the seasons, that might be the culprit.

Yes, there is a significant temperature difference.

coltin said:

Amazon Sword plants normally grow more in warm weather than cool weather. I have had mine outdoors in 40C water and they were fine so temperature is unlikely to be an issue unless it's a massive jump in temperature (10-20C over night) and that would probably kill the fish too.

It could be a change in water supply (as mentioned by MrGuppy) from your water company or they are adding something else to it in summer. Maybe contact the water company and find out if they change water sources during the year and if they add anything extra in summer.

That's interesting, as my experience is the opposite - my sword plant struggles in high temperatures, but thrives in low temperatures.

Snout said:

Do you use root tabs? They need a lot of food. My swords struggle without a couple of root tabs each every 3 months.

I do use root tabs, and I'll replenish them now since I'm not sure when I last did them.

FishArch said:

Agree with the above responses ++++
Here is what I would do: Make a list of what has changed. Things like the fish/bioload, lighting (even consider ambient light not just overhead artificial lighting), quantity/quality/frequency of nutrients, your water source etc.
Look for any changes, even seemingly inconsequential things like window shades or curtains being pulled to keep the room cooler. Massive water changes can affect the plant. Doing repeated water changes to stimulate spawning and at the same time, cleaning the filters can affect this plant if nutrients are not replaced. In summary, make a list and document the changes to prevent whipsawing.

Thanks for the advice. The temperature increase seems to be the main factor affecting my sword plant, but I suspect it's indirect - possibly related to changes in the water supply. I perform regular 40-50% water changes and clean clogged filters every week, which didn't affect the plants during winter. I'll investigate the water supply details today to see if they use a different source during summer.

When I said water perimeters, I was actually referring to the water's origin, rather than additives from the supplier. You see, river water characteristics can fluctuate with the seasons, and I'm assuming this might also be the case for other sources.

When you remove a lot of duckweed at once, it's possible the sword plant gets too much light and starts to bleach or burn, especially in warmer weather when the sun is stronger. I'm thinking this could be the issue, considering the temperature difference you mentioned.

Another possibility is that your sword plant is a specific variety that prefers cooler water, maybe one from higher altitudes.

MrGuppy wrote: ↑Wed Feb 19, 2025 4:26 pm I think there could be a temperature difference in the aquarium during the seasons. If not, I'd look into the water source - are you using tap water? Water parameters tend to change with the seasons, that might be the culprit.

I see, our water is definitely from a river, so that's probably the main issue here.

coltin said:

If you have duckweed on the surface and you remove it all (or a lot of it) suddenly, the plant could be bleaching/ burning due to the extra light. This would be more of an issue in warm weather where the sun is stronger than in cooler weather.

The other option is you have an unusual variety of sword plant that comes from higher altitudes and likes cooler water.

I'm not sure it's the bleaching from light, as the filter pushes the duckweed to the side where my sword is, and even when I remove some of it, the duckweed still covers the plant.

That might be the case, but this has happened with swords from two different suppliers, so I'm not sure that's the issue.

Thanks for all the help, guys!

My experience with Amazon swords is they struggle in plain tap water. I found they thrive in acidic and soft water conditions. I made the switch to RO water in my tanks and it made a huge difference. I also use a good plant substrate and strong 6500k lighting. Since then, my swords have been growing rapidly and even flowering.