Thank you. That is what I am trying to understand. Basically I have no fish no corals right now. I am going to get them over the years, but that is over the years, some skimmers I like says 180gal heavy stocked. I assumed this is lots and lots of fish I am really very long way from that point as I am moving slowly

but skimmer is good for 250 gal lightly stocked, so would that work for me . as I have 180 gal + 60gal sump. 180 gal - 80 gal taken by the rocks, and sump half empty. This makes my water amount about 130 gal all together. am I wrong ?
No ur absolutely right but remember what happens in this hobby.. once u have your tank cycled and setup .. even though u may start slow with fish first then cors, human impulsions will surely take over at some point where u will come across some fish or coral which u may not want to miss buying .. and soon u will have a nicely stocked tank.
Also each individual may have their own preference for feeding. I personally like to keep my fishes well fed, some may not.. while others wud be doing a healthy dose of manually feedjng corals separately. All that wud add to biol loads. So its best to plan for a bit bigger from start even though u wud move slow wth ur stocking.
In this hobby, the capital cost of equipment will always outbeat the price of livestock. And rhis is something u dont want to change as often unless u really intend doing a massive upgrade etc.
So my best thoughts to plan good enough from start even though u may not need it at begining.
A brighter way of lookkng at it, u wont be doing any wrong having a good effective skimmer take care of ur water quality from the very start. After all thats what we all need for our tanks to stay healthy n thrive..
Side note. U can keep adding addnly bio pellets in mesh bags or reactor ir marine pure bricks as space permits to be very safe in over stocking/overfeeding ur tank..
I have been using reef octopus supereeef 3000 int skimmer from reef supplies . And i love it. Keep in mind of the pump wattage consumption and thts one thing i like abt reef octopus skimmer pumps. The wattage is very reasonable as u will be keeping the pumps on for most part of the day n night minus feeding times..so keep the skimmer selection linked to the pump wattage comsuptilon too..
We dont want to keep paying ontario hydro our hard earned money.. thanks to K.Wynne..
Hope this helps..
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