Terrible Advice Tuesdays (T.A.Tues): Feed That Fish Or Else…

Terrible Advice Tuesdays: Fish need to be fed everyday or else they’ll die.

The rest of the story: Let me be really clear on 2 things first:

  1. The purpose of this post is not to advocate you feeding your fish as little as possible.
  2. The below advice is for healthy fish only. If your fish is sick or underweight, only follow the advice at the very end of this post.

Since we’re straight on those facts…

If you don’t feed your fish for a day, they aren’t going to instantly going to sink to the bottom of your tank and die. This fact is especially true if your fish are healthy and well-fed like mine. Furthermore, not feeding your healthy fish for 24 hrs isn’t going to put them in a weakened state that makes them susceptible to diseases.

Even certain high-metabolism fish like anthias will also be fine if you occasionally skip a daily feeding.

Skipping a daily feeding is not going to ruin your fish!

Sick fish advice: If you treating a sick fish, or you have a fish that is underweight, don’t skip the feeding. The fish needs all the food it can get and you don’t want to skip a day especially if you are medicating the fish’s food.




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Comments for this article (36)

  • david decarli says:

    good advice mark. fact is there’s ALLWAY’S a piece of leftover food algae or what ever. fish are natural scavengers and they will survive in a well established aquarium. but thanks for the great advice and keep the sick ones fed and medicated

  • Arthur says:

    I have heard that fish can go up to three days! That’s crazy, I couldn’t do it! I like feeding them to much.lol

  • david decarli says:

    hello mark. I was wondering if you had anything on proper water movement. (ie) where to place them and possibly why. you will have dead spots but where’s the best place and recommended gph what’s to much or not enough. thanks but someone like your self is the BEST place to get good info.

  • JasPR says:

    no question, people feed their fish way way too much. Fish don’t gain weight the way mammals do– they build fatty stores in the organs ( especially the liver) and that is a definite ‘life shortening thing’. Next time you see an elderly lady with a 40 pound cat on TV, think of the marine hobbyist that takes great pride in the ballon shaped pomacanthus or Tang.
    Some of the pellet foods are good in their nutritional balance ( assuming they are fresh) but are also fattening– if you feed this as a staple, feed less.
    And as Mark always points out– all of this ‘input’ is occurring in a ‘closed box’ where nothing is totally removed once put in– only converted to less offensive forms of nitrogenous waste.
    Finally, it is a fantasy to believe that a system exists that is totally self sufficient in converting all pollutants to ‘nothingness’. In the end, its just the matter of time interval to unacceptable pollution levels and slipping from the base readings of pure sea water. Two cents. JasPR

  • Geno says:

    For me this topic has always been my nemesis … How much to feed and how often. I too enjoy the excitement shown by my fish as I approach the tank. Feed me, feed me. And many of us fall victim to their “sad eyes” begging and wiggling in anticipation.
    My fish are probably feed more than appropriate, but I do skip a day now and then due to circumstances.
    Really enjoy this site and the interchange among subscribers.

  • Frank says:

    I work in a school and we have a tropical fish tower 200litres I have my own marine fish so have taken on this duty of feeding the fish. I feed them twice a day morning 0815 and night 1630 monday to friday they dont get fed over the weekend. And with weekends like just gone they are not fed for 3 days. I feel tight but on return every monday they are all okay. I have tried blocks but have always had trouble with them(fish deaths). I would appreciate anyones fought on feed blocks? I cant fit an automatic feeder due to tower design and being in a school of 700 + 11 -16 year olds not prepared to leave it open!!
    my marine fish are feed twice a day 7 days a week due to visit New York in August and not looking forward to leaving them!! (10 days) any idea? I looking into a auto feeder for this job (einheim)

  • Arthur says:

    Frank, your fish will be fine! Fish can go days with out being fed! I used the blocks once before, I got it from Pet-co. It worked fine, I didn’t have fish death, but it killed my carpet anamone though. Good luck! ( keep reefing)

  • JasPR says:

    For those of you who are scuba divers- you know the true nature of marine species– they are opportunistic feeders, plankton pickers and browsers. In the old days we would carry a can of cheese wiz underwater and create a feeding frenzy in a moments time. Frowned upon now, we have switched to clam and veggie ( silly humans) as a bait food. The point here is the immediate water is filled with scraps and in a few seconds it is GONE and the water is void of food again.
    I doubt a browser gets more than a tick tack of food in every ten bites– they work the area for as much as a football field to get daily nutrition. And think of energy expended to get that meal!
    Certainly marine fish deep in the throws of G.A.S. starve to death. But once the steroids and hormones fade and the fish acclimates, NO marine fish will starve to death based on lack of calories. they might , over time, die from nutritional insufficiencies. But not lack of calories.
    Each of us has a technique for feeding our fish. And with the advent of lighting that mimics nature and water surges that mimic the tides, I find it curious that we still feed our fish like goldfish. If we are going to ‘walk the walk and talk the talk’ we should be better at feeding technique.
    personally i will feed my fish in the early morning for several days in the row and then skip a few days. I often don’t feed on the weekends in winter when my fish room gets cooler and the heaters run the tanks at 72-74 F instead of the usually 76-78. When the room gets really warm and the tanks run at 78-82, I do not feed at all. Sometimes for three or four days.
    many of my fish are 5,7 and 10 years old. Nuff said.

  • bill sawyer says:

    i feed my tanks 3 times a week, mon. wed. fri. i use a 1/2 doz. or more of different kinds of frozen food from drs. foster & smith at a time, but i feed them over a course of a whole evening, when i start to see some food not being ate i stop feeding. i then let them eat off the reef… been doing this for years now w/o any problems. bill

  • Mark says:

    I do the same as Bill. Feed them 3X a week, MWF, a variety of stuff over about an hour. Never had a problem and have been doing this for years.

  • Jeff says:

    don’t have a reef tank yet- learning before I start. To anyone who wonders about fish not eating, think of this. My koi in the outside pond go anywhere from 4 to 6 months without food during winter months and the y survive just fine. So, why wouldn’t any fish be able to handle a few days without food? I don’t believe there is any problem.

  • Tron says:

    What about shrimp? Do they need to be fed daily?

  • Jerry says:

    I believe HOW you feed is possibly more important than how much you feed. With my reef tank, I feed several times a day but I use a small bit on the end of a chopstick. This amount means virtually none reaches the bottom, producing little in the way of excess nutrients

    With a good cleanup crew and a slow buildup of your biological filter, you can increase the amount you feed greatly. My nonphotosynthetic tank gets approximately 3lbs of food put into it per month, with only bi weekly 25% water changes. This was slowly built up, over time but shows that; with proper planning and patience, our systems are very adaptable. Due to the large amount of food that system receives, it allows me to maintain heavy feeding fish, like borbonius anthias and mandarins, in multiples, which would be impossible to keep in many tanks. The key is patience, of course. I do run a large skimmer and utilize probiotics to boost the bio filter but; other than that, simply took my time with the addition of nps corals

  • Josh says:

    I concur with Mark and Bill. I feed 3x a week over the course of about 45 minutes. My wife does feeds her freshwater tanks nightly, not too much though.

  • Jeff…keep in mind the koi’s metabolism slows way down during the winter months when the fish are largely dormant. Saltwater fish live in warm water climates and don’t go dormant so their metabolism is different.

  • Tron…shrimp don’t need to be fed. They are in your tank to clean up any bits of food left laying around.

  • Lisa says:

    I feed sparsely every evening in my FOWLR tank. However I feed 3-4 x daily in my seahorse tank. Different species have different needs. As a keeper it’s your job to know the needs of the fish you choose to keep. Some fish… Yes will be fine for a few days. Others… Maybe not, you should familiarize yourself with each one’s needs.

  • Roger says:

    I have a 50 gal reef with 11 little fish (damsels, a 6 line wrasse). They always seem hungry. I feed them 1 cube of brine shrimp, thawed and drained 6 days a week with Wednesdays off. You think that is too much food?

  • Barbara says:

    I have a fowlr tank of 2 triggers and 1 Dog Face Puffer and 1 sailfin tang. I just put my fish in and they are young. I heard feeding them 2 or 3 times a day fresh chopped prawn and crab etc… I have bought some vitamins to soak the food in(has not arrived yet). I add commercial emerald green and seaweed veggie clipped for the tang and also was told to add some garlic extract occasionally. Any of this wrong info?

  • Barbara says:

    Also I am trying to build up their strength from their time at the LFS

  • Tron says:

    Ok…sorry, I guess I should have been more clear with my question. I was asking about shrimp that are in a 28G nano tank that only has soft corals, mushrooms, snails and a blood-fire shrimp (no fish). I have been feeding 2-3 days per week with a small amount of Mysis shrimp….and it is really the only way I can get the little guy to come out from behind the live rock. I have only had this tank going for about 6 weeks, and since I am getting ready to take the family to Hawaii for 10 days, I didn’t want to add any fish until after we return. Do I even need to have my house-sitter worry about adding any food while we are gone?

  • Tron says:

    Also…forgot, but I have 3 hermit crabs in there too.

  • The importance of a balanced diet and stable feeding schedule can be a make or break for many hobbyists.
    What you’re feeding also determines how often you feed your fish.

  • kevin says:

    Depending on the fish i guess a lot of them could be without feeding for up to a week. If not overstocked. Look at wrasse and surgeonfish they eat all the time.

    I also wouldn’t skip feeding when introducing new fish or in quarantine. You don’t yet know the fish, so keep it safe and feed it.

  • Mark says:

    Hi Marc,
    Thanks for the clarification. I intentionally skip feeding once in a while. I did have a sick Blue/Green Chromis who survived vicious attacks by others in the tank when I first got it going. His tail was mangled, part of it missing, bitten off. I fed the tank generously and the fish recovered completely. It did cause an algae outbreak, small one, but a low price to pay to save a life. Things are fine now. Feed lightly twice a day.

  • JasPR says:

    I know this is not a site for debate and I’m not wishing to start an argument as there are other boards and venues for such things. But to set the record straight– a closed system can not turn all the things it receives into it, into nothingness. And even worse, the water itself is depleted of ‘things’ ( minerals, buffers and micro nutrient) as it interacts with biological systems ( like fish, clean up crews, various inverts).
    So this all results in AMBIENT levels of different elements and nitrogenous wastes. The idea is to keep certain ambient levels as undetectable and others as ideal or prime. As it turns out, this is like putting a 6’5″ man comfortably in a 5′ bed! Somewhere something is going to ‘stick out’! 🙂
    water changes reset the ambient levels or bring that back towards an ideal.
    On the other end of this model is what we actually do to ‘impact’ the water to begin with. Too many fish, an overactive biofilter, too much feeding– all put the closed system under a burden from the outset.
    Hopefully, some ‘food’ for thought. Best, JasPR

  • Good points JasPR!

  • Pam says:

    I I over feed I try to stop but just can’t my fish always look hungry.
    I know they always are. But I have a skimmer that can handle
    A 250 gal tank I have a 90. I also do 10 to 20 percent water ch
    Changes every week. My levels are always good and have
    Not had any problems

  • Pam says:

    Oh I also have a 55 gallon refugium on the tank

  • Lisa says:

    Mark how often do you feed your anthias?

  • William says:

    I feed my fish every other day, somtimes skip 2-3 days! I had a algae problem due to ober feeding a I have a reef tank and I used to extremly over feed. Now i just feed every other day and “feed the corals” once a month!

  • Steve says:

    I generally feed my fish tank 2 times per week. Sometimes I feed 3 times. I have had a yellow tang in there for over 10 years with this schedule. I see the fish eating small “fuzz” algae off the rocks all the time. Mandarins are constantly picking at the gravel, rocks and cracks. I sometimes go on vacation (no tank buddy) and the fish survive for up to 10 days with out a single feeding. But, there a lot of algae on the glass when I get back and I can see their “lip” prints from eating that.

    So, I can vouch for the fact that they do not need to be fed daily.

  • Lisa…My anthias get fed just as often as my other fish, which is every other day currently.

  • Lisa…My anthias get fed just as often as my other fish, which is every other day currently.

  • Kathy says:

    Thanks Mark for bringing up feeding!! Thanks JasPr for the technical (biological) end of the fishy story. I think we all have asked ourselves this very question, newbie or not. Clarification on this level is awesome, I could not find in depth feeding info that was consistent across the board and find hunting through Reef Clubs tedious and ambiguous. I prefer to stick to this forum which is far more informational and clear. Thanks again all.

  • Muhammad Ovais says:

    i have just added new fish inmy tank and they are not eating feed….give me some advice plzzzzzzz

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