I don't have any experience with k1 but maybe this can help until someone with experience chimes in https://www.monsterfishkeepers.com/forums/threads/cheap-and-easy-diy-fluidized-bed-filter.494441/Is there a general rule for how many liters/minute my air pump should be per liter of k1 media I am running?
Thanks for your input. I've always heard k1 as a self cleaning media and easy to maintain. Interesting to hear a differing opinion. I probably will have 90-100L of K1 total in the middle section of my 220 gallon sump. Probably going to go with a pondmaster ap 100 as it is cheap/decent. My sump is covered with green house panels so I;m hoping that will help with evaporation. Will also be plumbing in a float valve to auto top off the water. I do have another section with those yellow cylindrical ceramic media.Honestly I wouldnt mess with k1 cause it becomes a pain. But if you want the extra noise, and upkeep of k1, I ran roughly a turn over rate of 2x the volume of media. So if its 1 liter of media you would need 2 L /min per liter of media. When you have a lot more media (+30 liters of media) you can get away with less air per liter of media as the media will become a big mass and move. In part of a 75 gallon sump (the middle) I had about 50-60 liters of media roughly 15 gallons of k1 and had a 70 L/min pump and it worked pretty well. In theory tho, you can pump as much air in it as you want and itll still work fine and it will actually help keep the media clean.
Good thing was its only 60w's for 70 L/min but its so damn loud and the evaporation is insane. You'll be topping off the tank every 3-4 days, and you'll be surprised to see how much dead bio or beneficial bacteria they produce which needs to be cleaned out every 2 weeks to a month. In the beginning itll seem like too much air and once it ages and becomes less buoyant it'll seem like you need more air. Its a hard system to maintain for not much reward.
Some ceramic media achieves similar results, I always wanted to try the pondguru's ceramic media as he claims the middle is so dense denitrification bacteria thrive there and will consume a noticeable amount of nitrates.
looks liek ill be running a second mechanical filtration after the k1 compartment lol XDEveryone says that its self cleaning and its true, but they dont talk about where all the dead bio goes that got knocked off lol. All the dead beneficial bacteria that gets knocked off will accumulate rather quickly if the k1 is mature. For me it was in the actual k1 compartment on opposite sides of the air-stones and also in my heater/pump chamber which is the last place you want to see anything in the sump. Getting a vacuum going on your hands and knees using a cut 5 gallon bucket to be able pull a siphon got real old real fast for me.