Thanks All.... Many useful info and insights here... Just wondering how much of food is enough . 8-10 shrimps is of small size and shelled and deveined .
An fx5 has 900gph if i remember properly, so for a 180 tank, to me 400gph is way underfiltered. Try getting a filter or a bunch of filters that filters atleast 5-6 times your tank volume becuase when you pack it with media, itll become 3-4.
I could be fine, need to set up and run. Test you water parameters and let the results tell you if you need more filtration.
I don't like to get hung up on turnover or GPH, they are a guide but that's it.
I'll use my 150g as an example. It has 7 large cichlids all 9 to 11 inches and 5 5 to 6" clown loaches. It is filtered with 2 XP3 filters there actual flow rate is about 190 gph. so my turnover is only 2.53 times per hour. Now the XPs each have 2 liters of ehfisubstrat/biomax in them and keep the water params perfect.
Now I could change these filters out for two AC110s that will have actual flow of about 450 gph each. This will raise my turnover to 6 times per hour but since they will only hold about 1/4 of the bio media I currently have, I would not trust these to handle my current bioload.
I would think as large as the capacity is on the FX5 that a single one could effectively filter a 180g. I myself like to have redundant filtration so for me a single filter, not happening.
BTW my 180g has 2 XP3s and 2 AC110s filtering it though