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I've got a 20 gallon tank with Java Fern and Anubias, but the leaves are turning yellow. My light is a Nicrew ClassicLED, running 8 hours a day. Could it be too much light? Water params are good, 0 ammonia, 0 nitrite, 10 nitrate. Substrate is gravel, no CO2.

Yellow leaves could mean too much light, but Anubias is pretty chill. Maybe cut the light to 6 hours and see if it helps. What's the wattage on that Nicrew?

Anubias and Java Fern are low-light plants. Even if the Nicrew isn't super strong, 8 hours might be too much for them. Try reducing the photoperiod or raising the light a few inches. Also, check for algae, since that's a sign of excess light.

daxton6 wrote: ↑Fri Aug 22, 2025 11:03 pm Anubias and Java Fern are low-light plants. Even if the Nicrew isn't super strong, 8 hours might be too much for them. Try reducing the photoperiod or raising the light a few inches. Also, check for algae, since that's a sign of excess light.

Yep, gotta agree. My Anubias got crispy when I ran my lights too long. Dial it back and see if they perk up.

The Nicrew ClassicLED is 12 watts, which isn't extreme, but duration matters. Yellowing could also indicate nutrient deficiency. Are you dosing any fertilizers? Java Fern and Anubias feed from the water column, so liquid ferts might help.

I had the same issue with my Java Fern. Turned out it was a combo of too much light and not enough potassium. Started dosing Seachem Flourish and cut light to 6 hours, now it's green again. Maybe try that?

zenoir wrote: ↑Sat Aug 23, 2025 1:47 am I had the same issue with my Java Fern. Turned out it was a combo of too much light and not enough potassium. Started dosing Seachem Flourish and cut light to 6 hours, now it's green again. Maybe try that?

Sounds like solid advice. I'd also check if the leaves are getting direct light. Sometimes it's just a matter of shading them with floaters.

Thanks, everyone. I'll reduce the light to 6 hours and grab some Flourish. Appreciate the help!

Another thing to consider is the age of the leaves. Older leaves yellow naturally over time. If it's just the older ones, don't stress too much. New growth will tell you if the changes are working.

Yeah, lighting's tricky. I fried my first batch of plants by going full blast. Now I start low and slow, tweaking as needed. Less is more with these guys.