A 20 or 25 % change should be enough. It should get your nitrates down to less than 10ppm. Just check before you go to get your clean up crew that the ammonia and nitrites are fine. Nitrites are OK for fish, but I think they're bad for inverts.
If you're planning on getting a cleanup crew, keep a few hours free to acclimate them slowly. They need two or three hours of drip acclimating. I usually test the LFS water for salinity to see how far off it is from mine before I acclimate, just to see how slowly I need to drip. Snails process salt differently, and they're slow to acclimate. |