Why should I turn my skimmer back on?

[TWallace]

I've never been impressed with the amount of skimmate my skimmer produced (or any previous skimmer I've used on my system). My current skimmer is a Euro-Reef RS 100. My nitrates were always at or near 0. So I decided to see what happens when I turn the skimmer off for a month. As far as I can tell: nothing.



So, if after a month of going skimmerless the nitrates are still at 0ppm, is there any reason at all to turn the skimmer back on? During the month I performed one water change (2 weeks ago) only for the benefit of a smaller tank which needed a water change (I refilled it with water from my reef tank).

My livestock is about average for a 120g tank:

• 1 Powder Blue Tang
• 1 Small Desjardini Tang
• 2 Percula Clowns
• 1 Melanurus Wrasse
• 1 Juvenille Red Coris Wrasse
• 1 Gold Diamond Goby
• 1 Potter's Angel
• 3 Fire Shrimp
• 3 Cleaner Shrimp

I feed predominantly with flake food (Ocean Nutrition Prime Reef) using an Eheim auto feeder 3 times a day. About once a week I add a mix of various frozen foods to give the fish some variety in their diet. The tangs, angel and melanurus wrasse also eat a lot of nori from an algae clip which I restock daily. Yes you read that right, a melanurus wrasse eats algae from a clip. He's quite aggressive with it actually, and very fat as a result.

All corals look fine except the ones that are growing too close and stinging each other. All fish and inverts look healthy too. So...would you turn the skimmer back on in my case? If so, why?

[seapug]

If your water is nice and clear and nitrates are undetectable and pH, Alkalinity and Calcium are fine and everything seems healthy, then let it be. One thing a protein skimmer can do even when not producing skimmate is keep the water fully oxygenated. That can do a lot for pH stability and water clarity, but if you feel what you are doing is working for you, there's no reason to change.

[jimmy n]

As a safety net.

You're skimmer just doesn't have much to skim, so it produces very little.

If something dies behind a rock, or something else affects your system adversely, it would be nice to have that skimmer running. That way, when it starts producing, you know something is wrong.

[Randy Holmes-Farley]

IMO, whether to use it depends strongly on your other husbandry practices, which you do not mention. With some, it can be critically important (like vodka dosing). With others, it may be less important. Skimming helps aerate the water, removes organic toxins from corals and such, keeps the water from being as yellow, exports metals like copper that might otherwise build up, etc. If you do all those things some other way adequately well, then you may not benefit from it.

As much as for any other reason, I run my skimmer for aeration. I've tried without it as an experiment, and at the time the pH got too high when using limewater. The skimmer allows it to pull in lot more CO2 from the air. Keeping up O2 at night is also a big potential benefit that I think many people underplay, thinking (possibly incorrectly) that they have very good aeration.

FWIW, I discuss skimming here:

What is Skimming?
http://reefkeeping.com/issues/2006-08/rhf/index.php

[ludnix]

I have a very similar system compared to yours, but I think I'm stocked a little heavier. When my refugium started really taking off my skimmer has practically stopped skimming, I cannot detect any nitrates at all and everything is doing good. I keep the skimmer running though as mentioned earlier for a safety net. If something happened to my refugium and the plants stopped growing I need something else to help take care of the water quality.

[Michael]

well i think the guys have said enough about why skimming is a good thing, not much to add, personally i never switch mine off and imo believe its essential in marine aquaria

[madreef_7K]

I am very interested in this topic as well. A while ago I had a thread going where I was asking people if they turn their skimer off at night. The thread kind of got out of control with a lot of heated and passionate discussion but no real conclusion

After reading you experience, I will try this too. My NO3 and PO4 are next to nothing and I think he food (mostly frozen rotifers that I feed to my corals get pulled out by skimmer! I typically feed my tank after lights out (thats when I see the maximum polyp extention)

I'll follow this experiemnt for a week and let you guys know what happend to my tank!

[TWallace]

Thanks for the replies all.

Randy, I do not use vodka, sugar or any other "remedy" for reducing nitrates. I've never even tried those. I do have a refugium, but it has very little algae, which generally doesn't do well in there. I've got an urchin in there (banished from display due to frag stealing and knocking over corals). The urcin I'm sure has eaten some of the algae in the refugium. So I've got xenia in there as well as I've read it can also reduce nitrates to some extent.

The only algae that does well in my system is bryopsis which only grows inside the overflows. It's not present at all inside the display. Coralline also does very well. I've battled bryopsis since I had my old tank (55g). I upgraded to the 120 last summer using all the live rock and sand from the old tank, and the remaining bryopsis surely hitchhiked in from that. In the old tank I used Tech M to destroy the bulk of the bryopsis, but it hung on in high nutrient areas (the overflow box). I had seen a small tuft of bryopsis spring up on a powerhead in my 120 several months ago. After adding my powder blue tang, it disappeared and has not been seen since. I don't know if the PBT ate it (I kinda doubt it given the fact that nothing seems to eat bryopsis), but I'm content that it only grows in the overflows now.

I do not use limewater anymore, though I used to. I've switched to using calcium chloride and baking soda to keep calcium and dKH stable at around 400ppm and 9dKH.

My system contains around 150 pounds of live rock, which I think may plan a part in my low nitrates. Corals are a mixture of mostly SPS, several toadstool leathers, thousands of zoanthids and some small LPS (acan, micro, candy cane, small polyped goniopora).

[TWallace]

Just thought I'd update this. Another 10 days have gone by, nitrates are still 0. I have not done a water change during that time, either. The water has no yellow tint.

Here are a couple pics:

[Electrobes]

Glad to see everything looking good. I have been on both sides of this issue, and currently my skimmer has been taken off (Mainly because of micro bubble issues). My nitrates consistently read zero, and thankfully my other parameters are exactly where I want them, and have been for the past month and a half.

Even if the skimmer isn't exactly needed, as dictated by the parameters, I would still keep it on mainly for the aeration and the "just in case" scenario... spawning, sudden fish/coral death, food dispenser goes nuts, etc. As we all know.. we can never have enough back ups in this hobby.

The following paragraph is useful for those that have that extra space to have a skimmer, but if it is a hinderance, then I would do without a skimmer... again with the support of the test kits.

[Ebisan]

Skimmers are not necessarily a must have but it's a nice to have. The stuff it pulls out is something I would not want to put back into my tank.

[Aj Flip]

ya your system looks really healthy, if i were u i would prolly put the skimmer on a timer then for the night in case something dies, it gets skimmed.

are you running carbon?

[Phillybean]

I would say turn your skimmer on for a week.

Afterwards if you'd be willing to dump whats in it back into the tank, no need running it.

[MM WI]

Concentrating on nitrates as a measure of the function of skimmer is not a valid measure. I know there have been several treads on this site that discuss skimmers in terms of nitrates but this is not the reason you need a skimmer or really the intended function of a skimmer to any extent. Please don't waste a post explaining that the nitrogen component of the organics eventually become nitrates. I am well aware of that. If a skimmer is the primary route of nitrate reduction your system is not complete. A well designed reef will run zero nitrates because of biological anaerobic reduction of nitrate to Nitrogen and oxygen gas. What you are demonstrating is not that a good skimmer will not help your tank, you are demonstrating how silly it is to trying to circumvent the nitrogen cycle in your tank. Your tank looks great so you obviously have a well designed system. You may be able to get away with no skimmer if you are not feeding too heavy. It is the dissolved organics that I would worry about the most. Some organics will not breakdown quickly and will have toxicity. I like a good experiment but I would not do on such a valuable collection of life in great looking tank.

I could not get away with no skimmer given the amount of after dark feeding of LPS I do. You maybe able to pull it off. I am guessing there will be some benefit on one hand but the cost on the other maybe be too great.

If you continue your experiment please keep posting. I would be more interested in any trends in ORP as time goes by and pictures of the animals.

- Mark

[weluvfish54]

in my 120 gallon i have a lighter bioload of a lionfish, eel, and angel fish. i do not and have not run any sort of skimmer. the water is clear as day and no nitrates ever. i do feed silversides and mysis every other day and no probs.

[TWallace]

That's pretty impressive weluvfish54. You may have fewer fish than I in the same size tank, but your lionfish and eel are surely much messier eaters than anything I have.

[TWallace]

Aj, no I do not run carbon. My sump contains 2 heaters, a return pump and a refugium section, which currently contains very little algae. Just a couple of fronds of fern caulerpa that my urchin refuses to eat. He's devoured the chaeto and grape caulerpa that used to live in there. It's turned into a xenia farm in the refugium.

[weluvfish54]

tw, they actually arent very messy, they eat em whole ;D

[johnny313]

if you have it, why not use it??? i can see if you didnt have one and had no money to get one but you have it???....

[TWallace]

Originally posted by johnny313
if you have it, why not use it??? i can see if you didnt have one and had no money to get one but you have it???....

I'm trying to find out if there is any advantage in running one in my system. So far I'm not seeing one. I've noticed no change in my corals/fish and I'm not having an issue with nutrient export. So...why use it? I like having it off, it's much quieter and not wasting electricity.

I don't think owning an item is itself a reason to use it. If I still had an undergravel filter from an old system, would I be silly in not using it? I think not. I think a lot of people are under the impression that protein skimmers are an absolute necessity and that all tanks will benefit from one. I'm not so sure.

[TWallace]

Originally posted by weluvfish54
tw, they actually arent very messy, they eat em whole ;D

I didn't mean just the messiness of eating. I meant what comes out the other end .

[saltaholic]

I would use it simply for the gas exchange. I hate my skimmer and wish I didn't have to use it. It doesnt really pull anything except for the coral food I just added. Every time I feed I have to make sure its not going crazy, etc.. Like the previous post stated its nice to have in case. However if I leave it off for a amount of time my ph drops. In fact I have thought of running a air line outside to increase O2 levels. I know of many tanks that are keeping some very delicate animals with out ever having a skimmer. What works for you and your tank is what is important.

[Pacific Reefs]

You may need it when the fish get bigger.

I ran without a skimmer for a few months and developed hair algae. It's always your choice but I would just keep it since it's not oversized and therefor not "overskimming" your water.

[dbrann11]

I think TWallace and MM's points are both valid. As a newb you're told you need a protein skimmer, and as a newb I can say this... husbandry skills take time to develop and a good skimmer is probably quite beneficial for someone with less than stellar husbandry. However skimmers haven't been around forever and there are plenty of beautiful examples of reef tanks with no skimmers, so obviously it is not neccesary.

For the more experienced keepers a skimmer is probably not a required piece of equipment but provides piece of mind and/or the ability to carry a higher than otherwise allowed bio-load... OR more difficult to keep inverts.

I ran a seaclone for 2 years, which worked when it wanted to... just upgraded to an octopus and it's pulled 3 cups of crap out of my 44g in 2 weeks. The tank looks the same... but for me I feel there is a benefit to a good skimmer.

[TWallace]

My pH is staying constant between 8.1 and 8.2 which seems perfect to me. I don't understand the relationship between oxygenation and pH. I do have pretty good gas exchange on the top of my tank from powerheads creating surface turbulence. I imagine the dual overflows to the sump help to add oxygenation, too.