Hi All. I have a 55 gal tank with an eheim 2074. Filter is rated for 92 gal. In one manual the pump is listed at pushing 396 g/h. In another manual the flow rate with media is 154.54 g/h. I also ordered a co2art se regulator kit. And light is the fluval plant 2.0 Will be keeping 10 pearl gourami and a school of harlequin rasbora and a group of panda Cory.
Now here I think I will be all set but I read that flow rate should be 10 x the tank size. I have a couple of small power heads but is that needed? Why does this filter show its good for a 92 gallon tank if the rule of thumb should be 10 x the tank size? What should I do now?

Filter ratings can be used based on processing biological waste, but for plants / fish avoiding dead spots in the tank are key.

Usually 10x turnover rate listed by the filter manufactures roughly = 5x actual tank turnover after media / other flow restrictions are considered.

Your filter is more than capable of processing all the biological filtration the tank needs, but it's the flow and turnover you are missing to avoid any dead spots in the tank and keep all of the water moving around consistently.

Thanks for the reply. I will research where to place power heads I think I have an aqua clear 20 and 30 from 20 years ago. I might be only keeping some crypts which don’t grow tall so maybe i can place the heads up high pushing down.

Once you have the tank scaped, planted, and filled you will be able to see where the water is not moving much/at all. Then you know where to put powerheads if you want to go that route.

Good idea. Thank you!