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My tank's phosphates are sitting at 0.25 ppm, and I'm trying to avoid using chemical removers. Anyone got tips for lowering them naturally? I've got a 75-gallon mixed reef with softies and LPS, running a protein skimmer and chaeto in the sump.

Yo, chaeto's a solid start, but you gotta up the harvest frequency, like every week or two. Also, cut back on feeding, bruh. Overfeeding's the usual suspect. What's your current feeding routine?

reeflad wrote: ↑Sun Aug 17, 2025 11:57 am Yo, chaeto's a solid start, but you gotta up the harvest frequency, like every week or two. Also, cut back on feeding, bruh. Overfeeding's the usual suspect. What's your current feeding routine?

Agreed on the chaeto. I'd also recommend adding some macroalgae like Ulva or Gracilaria to the display. They're efficient at phosphate uptake and can be easily removed when overgrown. What's your lighting schedule for the chaeto?

I've had success with increasing water changes. Doing 20% weekly with RODI water dropped my phosphates from 0.3 to 0.1 ppm in a month. Are you using RODI for top-offs and changes?

Dude, try adding some phosphate-binding media like GFO in a reactor. It's not 'natural,' but it's way better than letting phosphates mess with your corals. Also, what's your nitrate level? High nitrates can make phosphate issues worse.

otter9 wrote: ↑Sun Aug 17, 2025 3:20 pm I've had success with increasing water changes. Doing 20% weekly with RODI water dropped my phosphates from 0.3 to 0.1 ppm in a month. Are you using RODI for top-offs and changes?

Yep, water changes are clutch. I'd also check your RODI filters—if they're old, they might be leaching phosphates back into the water. How often do you replace them?

Honestly, just feed less and let the chaeto do its thing. My phosphates were sky-high until I cut feeding to every other day. Now they're steady at 0.05 ppm. Whatcha feeding your tank?

Consider adding a refugium if you don't already have one. A well-stocked refugium with chaeto and pods can significantly reduce phosphates over time. What's your current sump setup like?

stardog wrote: ↑Sun Aug 17, 2025 1:57 pm

reeflad wrote: ↑Sun Aug 17, 2025 11:57 am Yo, chaeto's a solid start, but you gotta up the harvest frequency, like every week or two. Also, cut back on feeding, bruh. Overfeeding's the usual suspect. What's your current feeding routine?

Agreed on the chaeto. I'd also recommend adding some macroalgae like Ulva or Gracilaria to the display. They're efficient at phosphate uptake and can be easily removed when overgrown. What's your lighting schedule for the chaeto?

Ulva's a great call. I run my chaeto light 24/7, but some folks swear by a reverse photoperiod. Either way, consistency is key. How's your chaeto growth rate?

Thanks for all the suggestions, everyone. I'll try harvesting the chaeto more often and cut back on feeding. Appreciate the help!