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My Frogbit has been in my 20-gallon tank for weeks, but it's not spreading like it should. I've got a Nicrew light on for 8 hours a day, and my water params are good, 0 ammonia, 0 nitrite, 10 nitrate. What's the deal?

Frogbit can be picky about flow. If your filter's too strong, it might be getting tossed around too much. Try corralling it with some airline tubing or lowering the flow.

Lighting could also be the issue. Nicrew lights are decent, but Frogbit prefers brighter conditions. You might need to bump it up to 10 hours or consider a stronger light if the plants aren't getting enough PAR.

Mine didn't grow till I added some root tabs. Maybe your substrate's lacking nutrients? Frogbit's roots suck up a lot from the water column too, so liquid ferts might help.

daxil wrote: ↑Wed Aug 27, 2025 5:00 pm Lighting could also be the issue. Nicrew lights are decent, but Frogbit prefers brighter conditions. You might need to bump it up to 10 hours or consider a stronger light if the plants aren't getting enough PAR.

I agree with this. Also, check if your light's spectrum is right. Frogbit hates cool white LEDs, it's all about that warm, reddish tone.

Thanks for the tips, everyone. Gonna try reducing the flow and upping the light duration first. Appreciate it!

Yo, don't sleep on water hardness either. Frogbit's kinda finicky with super soft water. If your GH is below 4, it might struggle. Test it out and maybe toss in some crushed coral if it's too low.

Mine took forever to take off, but once it did, it went nuts. Patience is key, but yeah, tweak the light and flow like others said. Also, make sure no fish are nibbling on it. Some species, like goldfish, will wreck it.

If you're dosing liquid ferts, check your potassium levels. Frogbit can show stunted growth if it's lacking. A balanced fertilizer like Thrive or Easy Green usually covers it.

Frogbit growth is often hindered by excessive surface agitation. Ensure the water surface is calm. Adjust your filter output or add a baffle if necessary.