First of all, you've seen sea foam. That's what a skimmer makes. Foam. What is it? Protein waste, amino acids---fish poo. We call it skimmate. It's color ranges from brownish watery (we call that skimming 'wet', which you do if you have something you want to move out in a hurry); to nearly black green/brown (skimming dry).
The most efficient skimmers produce a lot of foam. A 'venturi' or air-supplied (via tube) skimmer can really froth. An air-injection model may just have an air intake (which you have to keep cleaned and clear and turned ON.) They can be mounted inside the sump or hung onto it.
Clean a new skimmer with vinegar: it takes off the manufacturing oils, so it will help the froth rise in the column to the collection cup. Likewise---clean the column when foul.
Sometimes skimmers 'spit', or vomit water wildly when the water level has changed abruptly, notably on re-start. I cured my Coralife 200 of this messy habit by mounting some snippets of air hose onto the nipples of the two intake points...and keeping the ends of the hoses from accidentally getting into the water, which can cut off your bubbles/froth. This means that any overflow is directed back into the sump and not onto my floor.
I recommend getting a modest-priced skimmer of about twice the system water capacity---eg, I use a 200 on a 105 gallon tank with a 30 gallon sump, a little underpowered, but does nicely.
Vinegar or other carbon dosing can hype a skimmer's action: old tanks may consider this measure, but do it ONLY when in possession of a chart of how much how fast.
New tanks are so clean they have no skimmate to give, so if you are just starting out, don't be shocked that you get nothing much.
You may be advised to 'tune' your skimmer when, say, doing a lights-out to kill cyanobacteria [an operation in which a tuned skimmer is important, to get the gunk out fast.] This just means to be sure it's operating at top capacity. To 'tune' mine, I dial the control on it until I can just barely see 'water' as opposed to froth at the bottom of the clear column, where the froth rises. If I let the froth rise very fast, it skims 'wet'; but I'll have to empty the cup real soon and attend it often. If I skim 'dry,' which is usual, I see that the froth rises slowly, and makes my required maintenance once a week, not once every few hours.
It's a cranky kind of instrument, and is subject to behavior changes with water level changes. It may also not function correctly if set too deep or too shallow relative to the water level. I've personally been happier with the hang-on sort, with my funny little 'relief' tubes that keep the spitting confined to the sump. But the larger skimmers may have an overhead problem---ie, being too tall to let you lift the cup off upward. Look for a screw-on cup arrangement that lets you lift the cup off with much less vertical space---I can get mine off sideways with about 3/4 inch lift as I unscrew it.
Ultimately you do need one, particularly as your tank ages and stuff accumulates. SPS requires you have a good one, because SPS needs very clear water. LPS and softies are more forgiving of skimmer quality, but even with very few fish, the load will stack up on you.
Other observations and suggestions are welcome.
The most efficient skimmers produce a lot of foam. A 'venturi' or air-supplied (via tube) skimmer can really froth. An air-injection model may just have an air intake (which you have to keep cleaned and clear and turned ON.) They can be mounted inside the sump or hung onto it.
Clean a new skimmer with vinegar: it takes off the manufacturing oils, so it will help the froth rise in the column to the collection cup. Likewise---clean the column when foul.
Sometimes skimmers 'spit', or vomit water wildly when the water level has changed abruptly, notably on re-start. I cured my Coralife 200 of this messy habit by mounting some snippets of air hose onto the nipples of the two intake points...and keeping the ends of the hoses from accidentally getting into the water, which can cut off your bubbles/froth. This means that any overflow is directed back into the sump and not onto my floor.
I recommend getting a modest-priced skimmer of about twice the system water capacity---eg, I use a 200 on a 105 gallon tank with a 30 gallon sump, a little underpowered, but does nicely.
Vinegar or other carbon dosing can hype a skimmer's action: old tanks may consider this measure, but do it ONLY when in possession of a chart of how much how fast.
New tanks are so clean they have no skimmate to give, so if you are just starting out, don't be shocked that you get nothing much.
You may be advised to 'tune' your skimmer when, say, doing a lights-out to kill cyanobacteria [an operation in which a tuned skimmer is important, to get the gunk out fast.] This just means to be sure it's operating at top capacity. To 'tune' mine, I dial the control on it until I can just barely see 'water' as opposed to froth at the bottom of the clear column, where the froth rises. If I let the froth rise very fast, it skims 'wet'; but I'll have to empty the cup real soon and attend it often. If I skim 'dry,' which is usual, I see that the froth rises slowly, and makes my required maintenance once a week, not once every few hours.
It's a cranky kind of instrument, and is subject to behavior changes with water level changes. It may also not function correctly if set too deep or too shallow relative to the water level. I've personally been happier with the hang-on sort, with my funny little 'relief' tubes that keep the spitting confined to the sump. But the larger skimmers may have an overhead problem---ie, being too tall to let you lift the cup off upward. Look for a screw-on cup arrangement that lets you lift the cup off with much less vertical space---I can get mine off sideways with about 3/4 inch lift as I unscrew it.
Ultimately you do need one, particularly as your tank ages and stuff accumulates. SPS requires you have a good one, because SPS needs very clear water. LPS and softies are more forgiving of skimmer quality, but even with very few fish, the load will stack up on you.
Other observations and suggestions are welcome.
