When to upgrade skimmer?
 

What are the tell tale signs that you need to upgrade your protein skimmer? I have a Tunze 9410 on my 150g. It seems to be keeping up OK even though it's a little undersized. I think that I'll need to upgrade at some point - what are the symptoms that I should be looking for?

It really depends on your overall setup.
Skimmers only remove a small percentage of doc's, so if you have a substrate or coral overgrowth, detritus can build up, so a better solution may be to make sure that you have good water circulation and a clean substrate instead of getting a bigger skimmer.
Good water circulation will allow bacteria to digest DOC.
Thinning out coral growth will allow better water circulation.

If everything else is optimal but your tank is still a slimy algae covered mess then it would be a good idea to upgrade the skimmer. But as Mitch suggests, adequate water flow throughout the display and the rest of the system is critical for getting waste to the skimmer in the first place. A friend of mine once had a very clean running 500gal and then downgraded to a 75gal that was always filthy. He used the same massive skimmer from the 500 but the water flow throughout the new system was so poor that very little of the waste ever made it to the skimmer to be removed.

I'd be upgrading the skimmer if I see nitrate and phosphate creeping up despite my best attempted to lower it. Some people use things like biopellets to help counteract, but even biopellets work best with a really good skimmer.

I've never been a fan of Tunze skimmers (way underpowered IME & IMO). I much prefer oversized skimmers to undersized ones (unless you are willing and able to do very frequent water changes).

In my main display, I have been going against conventional wisdom and added a big Deltec skimmer without taking out my original Deltec skimmer. Together they pull out a lot of crap from the water column, but I feed frequently so the fish and corals don't suffer any negative effects from overskimming. I'm probably at three times the skimmer/water volume capacity.:wink::biggrin:

Anthony

That's all very good information. Thank you! I've got very good circulation in the display and my nitrates/phosphates are consistently at 0 so I guess I'm good for a while.

Truth be told I think I'm trying to validate the purchase if a new skimmer. This Tunze seems to work well. It's the only skimmer I've owned that actually worked so I can't compare it to anything. My only complaint is that it's a little louder than I was expecting.

Truth be told I think I'm trying to validate the purchase if a new skimmer

I have a hard time as well not spending money If i can justify it to the wife somehow :)

Noise would be enough jusitication for me... And more so for the wife!!