when do I add a skimmer??

[4FordFamily]

Honestly I think you only need a skimmer if you have a heavily stocked with lots of nutrient import. In the past I have had them on tanks with very little bio-load and the skimmer took out mostly just water that was a little green tint to it. Also you can get the biggest skimmer you want but after a certain point its just wasting money, if you buy a skimmer that can handle a 500g heavily stocked tank and you have a 200g tank then its just over kill and not really doing anything extra Vs. buying a skimmer that can handle a 250g heavily stocked tank.

I respectfully disagree, you can adjust the skimmer to skim dryer and remove nastiness. Especially after water changes and events that stir up the substrate they remove the disturbed detritus and dissolved organics from the water column very quickly which decreases the negative impact on the livestock in the tank.

The oxygen provided is immensely useful, and they rip out so much nastiness! My skimmers are placed on very overstocked tanks but remove almost an entire collection cup (my collection cups are enormous for my large skimmers) of dark brown even black nastiness each day or every other day. I can't imagine leaving that in the water column!

But you do bring up a good point - that if lesser stocked they may be less useful. While true I venture to guess many people both slack on husbandry and overstock their tanks. I at least admit that I definitely overstocked my tanks and at times don't do water changes as I should! I suspect we all need to have a plan B sometimes!

I also accredit much of my success with difficult and expert only fish to overskimming as well. Both the oxygen and cleaner water no matter how you slice it.

 

[Harold Green]

When I set up my 210 last year I bought a bubblemagus 2200 skimmer. It's rated for just under 400g. Has worked very well for me and was the lowest cost large skimmer I could find. I feed the tank daily and it pulls out some really brown/green nasty stuff.

 

[4FordFamily]

If you feed nori (and you should daily if you have tangs and angels) it will often deteriorate a bit before they finish it all. The skimmer will remove this excess before it turns to nitrates!