Who Gives A Fish Forums

How long should I leave my lights on for a planted tank with Anubias and Java Fern? I've heard conflicting advice, some say 6 hours, others say 10. My tank is a 20-gallon with a Nicrew light, and I'm dosing Easy Green once a week.

It depends on your light intensity and plant needs. For low-light plants like Anubias and Java Fern, 6-8 hours is usually enough. Too much light can cause algae. What's your nitrate level? That can affect growth too.

I run mine for 8 hours, split into two 4-hour periods with a break in between. Seems to keep the algae down and the plants happy. My Anubias are thriving in a 30-gallon with a Finnex light. Maybe try tweaking your schedule?

I've had success with 7 hours. My Java Fern started melting when I did 10, so I cut it back. Maybe start with 6 and increase if they're not growing?

Yo, I do 7 hours straight, no breaks. My Anubias are chill, no algae issues. Tank's a 15-gallon with a cheap LED. If your plants look good, don't mess with it too much.

Thanks for the advice, everyone. I'll try 7 hours and monitor the plants. My nitrates are around 20 ppm, so that should be fine.

I disagree with the split lighting idea. Plants need consistent light to photosynthesize properly. Stick to a single block of 6-8 hours.

raysun wrote: ↑Fri Jun 06, 2025 8:11 am Yo, I do 7 hours straight, no breaks. My Anubias are chill, no algae issues. Tank's a 15-gallon with a cheap LED. If your plants look good, don't mess with it too much.

Same here, but I do 6 hours. Less light means less chance of algae, and my plants are still growing slow but steady.

My tank's a mess, but the plants are alive. I leave the light on whenever I remember, lol. Probably not the best advice, but it works for me.

kaylornix wrote: ↑Fri Jun 06, 2025 8:47 am Thanks for the advice, everyone. I'll try 7 hours and monitor the plants. My nitrates are around 20 ppm, so that should be fine.

Let us know how it goes. Adjusting light duration is trial and error sometimes.