From zero bioload to heavy: skimmer sizing for a new tank.

[Kevin Jaako]

Hey everyone! I'm putting together my first tank right now and selecting a skimmer is my last big hardware decision while I'm busy painting & plumbing. Now, I'm not looking for particular skimmer recommendations here; there are enough of those threads out there... I'm trying to understand how to approach skimmer sizing for a NEW tank.

I plan on adding livestock nice and slow (I'll try, anyway ), but that's going to mean my bio-load is going to take a meaningful amount of time to go from zero to tiny to low to medium... how do you size a skimmer for that? Do I buy for now? or buy for my eventual bio-load?

A few things I understand to be true:
- Buying an oversized skimmer is generally regarded to be a good thing
- Buying a WAY oversized skimmer creates problems dialling it in, as it can't reliably hold a foam
- Manufacturers state size ratings in different ways, so pay attention to neck size, air flow, etc.

So – I'm setting up a 80g column tank. It's 24" X 24", and 32" tall (yes, I have long arms). I've googled and BRS'ed and LFS'ed enough to know what skimmer i'd LIKE to throw on a tank of this size, but what about right now?? My bioload is going to be insignificant for a while, isn't that going to play havoc with an 80g-rated skimmer?

Does anyone get temporary skimmers while they fill out their livestock?? Seems easy enough to buy a used skimmer for 6-9 months while my bioload crawls out of nano territory? Or am I overthinking things?

KJ

 

[mcarroll]

No temp skimmers and no skimmers "for the next tank" either.

There's really no harm in an under-sized skimmer...the limit is how often you'll be willing to empty the cup. A cup with a drain mostly eliminates that limit.

The problem with a skimmer that's too large is that it doesn't skim...it won't put skimmate into the cup.

So....

IMO, buy the skimmer for the tank size rather than for the bio-load.....match it's flow rate to the tank's return rate (aka about 4x turnover). No need to oversize in any real way.

For example (sub any maker you prefer):

A Tunze 9410 (up to 265 gal) would be great for a well-stocked 80 gallon...

DOC Skimmer 9410
Recommended for salt water aquariums up to 1,000 liters (265 USgal.). Immersion depth from 140 to 2... mehr

9410.000

329.99 USD

The 9415 (up to 400 gal) would be pointlessly huge though...

DOC Skimmer 9415
Recommended for salt water aquariums up to 1,500 liters (400 USgal.). Immersion depth from 100 to 2... mehr

9415.000

584.36 USD

While the smaller 9004 would be underrated (up to 65 gal)...

Comline® DOC Skimmer 9004
Recommended, depending on tank load, from 60 to 250 liters (15 to 65 USgal.) of sea water. Immersio... mehr

9004.000

153.77 USD

...if you added the "holiday cup" with a drain hose...

Skimmer cup holiday
for DOC Skimmer 9004, with appropriate hose connection and 2m (78.7in.) silicone hose. Provides the ... mehr

9004.145

40.09 USD

...what's the problem if it skims like a demon 24/7? Hook it up to a 5 gallon bucket or even a floor drain.

 

[DesertReefT4r]

Size and buy once. If plan to oversize the skimmer for your tank, lets say plus 1 skimmer size, just get that skimmer from the start. If it does not skim well wirh a lower bio load thats ok bur I doubt that will happen. I have a RO NW 150SSS on a 75g 20L sump that is cycling with just cooked and cured live rock and sand no live stock or CUC. Adding frozen krill to cycle. That skimmer is holding a good foam head, skimming very dry for now. Rated for 110g medium bioload and I have ~70g total basically no bioload.