An observation about fish digestion

untamed · #1 01-03-2009, 12:31 AM

For lunch, my fish usually get some pellets (Formula 1 and 2). Recently, I ran out of F1 (red) and the fish have been getting only F2 (green) for lunch for a few weeks.

Today, I finally got out and purchased some F1 pellets. So the fish got some red F1 pellets today at about 2PM.

At around 5PM, I happen to be watching the tank when the Lookdown pooped....red.

That means that lunch passed completely through the Lookdown in about 3 hours.

Fish are clearly designed to eat constantly. Food for thought for anyone who feeds only 1x per day.

banditpowdercoat · #2 01-03-2009, 12:36 AM

I mix my Form 1 + 2 in one canister. feed them both at once

Ya, through a fish just like Hot wings in me LOL I have acctually never seen my fish poop. Maybe they self concious of pooping in public LOL

dsaundry · #3 01-03-2009, 12:48 AM

Quote:

I mix my Form 1 + 2 in one canister. feed them both at once

Ditto

justinl · #4 01-03-2009, 03:04 AM

Well, I think it is impossible to generalize such a function accross all fish. Some fish, like lions are designed to go out and hunt, eat a very big meal and let it sit for weeks. In fact feeding every day can actually harm some fish in the long term like lions... if they accept the food and even if they beg. General trend is that large ambush predators do that, but peaceful planktivores like anthias eat constantly. Predators like lookdowns fit too, because they are mid-water fish with high metabolisms and eat constantly in the wild. I find that knowing a fish's life history in the wild is a very helpful tool in this hobby. But yes, food for thought indeed for those with fish that fit the criteria. good observation.

tang daddy · #5 01-03-2009, 05:41 AM

I use to feed my fish every other day sometimes 2 day break however as much as they can eat cause I thought that was the way they survived in the wild, I guess partly to blame was the national geographic movies on reefs and oceans. Anyhow I also thought that they would digest their food thoroughly if they were fed heavy every other day. Now I have to say I feed my fish everyday and do waterchanges once a week compared to once a month. To be honest sometimes I forget like 4-6 times a month and find that they are still healthy as they eat as much as they can when they do. A reason I have to feed so much is that some fish in my fowler eat fast while others starve so by feeding alot everyone gets a piece. Tangs and rabbitfish IMO seem to eat and ship$ constantly while my other fish get full and stay that way for a few days. At any rate if I only ate every other day I wouldn't be a happy camper so why do it to my fish?

GreenSpottedPuffer · #6 01-03-2009, 06:15 AM

I work from home, so I feed about 4-5 times a day, sometimes more. Small feedings though. I find the only downside is that now every single time I go near the tank, the tangs think its food time.

untamed · #7 01-03-2009, 07:04 PM

Quote:

Originally Posted by justinl

Well, I think it is impossible to generalize such a function accross all fish. Some fish, like lions are designed to go out and hunt, eat a very big meal and let it sit for weeks. In fact feeding every day can actually harm some fish in the long term like lions... if they accept the food and even if they beg. General trend is that large ambush predators do that, but peaceful planktivores like anthias eat constantly. Predators like lookdowns fit too, because they are mid-water fish with high metabolisms and eat constantly in the wild. I find that knowing a fish's life history in the wild is a very helpful tool in this hobby. But yes, food for thought indeed for those with fish that fit the criteria. good observation.

Yes, of course there are differences. I suspected that food went through my fish quickly, but I was surprised that it was only 3 hours.

As you know more than me...Do fish actually store fat? Assuming that they do, it is another suspicion of mine that fish don't generally store fat very well. As they may be wired to eat constantly, there is no reason to store energy for long periods of non-eating.

I often joke that my fish are "fat", but I'm not so sure that they actually are. It also seems to take a long time for a thin fish to put on weight, even when they seem to be eating a lot.

justinl · #8 01-04-2009, 10:11 PM

that is a very good question and I can't really answer it. I think it is safe to assume it will depend greatly on the life style of the fish. Lookdowns and tangs probably store fat less than a grouper for example. Probably not stored as fat either but as soluble lipids in their blood; im just speculating now though. i would expect fat in a fish to serve as insulation but not as an energy store. I could be wrong though. wonder if it might screw up their buoyancy after a point?