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Ruth
09-15-2006, 06:09 PM
This might sound like a stupid question but I can't remember ever seeing in asked or answered. If you have a system with no fish - only corals and clams - what would be the effects of this - so no fish - no feeding - no fish waste. Would you have to suppliment the system with an additive of some sort like Phyto for softies and some LPS. What about if you only have SPS? Are just regular water changes and maintaining good water quality enough for these corals to get what they need to grow and thrive?
I know I should probably be able to figure this out but have never had a system with no fish. The only inverts would probably be some snails although I may consider an anemone.

danny zubot
09-15-2006, 06:22 PM
No fish would mean less waste for sure. But there are other things in a reef tank that create waste.The very bacteria that break down the waste even produce their own, but since there would only be a minimal amount of waste being produced, a minimal population of bacteria would be present. I think the effect would mean less waste, but not eliminated. One would think that this would be a possitive thing, but I can't help but wonder if corals there is some kind of down fall?

I'll stop rambling now, too much coffee this morning.

Ruth
09-15-2006, 06:41 PM
Well that's the thing - I keep thinking there must be a downside - granted you water quality would probably be easy to maintain as you are not introducing waste into the system but.................... hmmmmmm

Jaws
09-15-2006, 06:41 PM
There are a couple fish that can offer positive effects like six line wrasses for instance because they eat some parasites on corals but for the most part no fish would mean a healthier system. When you have to feed fish you put food into the water that releases nutrients before even being eaten. Then the fish eat the food and eventually release waste into the water not only from the food but also from their own bodies. That is partly why some of the more experienced reefers with thriving tanks usually have very few fish in comparison. I've always wanted to leave a tank for a year without any fish to see just how much of a difference it would make but then one trip to the LFS seems to always foil that plan. I imagine a reef would establish itself way faster without any fish introduced to it as well; less nutrients, more pods, etc.

It's kind of unfortunate since part of the attraction of a natural reef is the unbelievable amount of activity because of the thousands of fish hovering about.

Beverly
09-15-2006, 07:03 PM
I had a fishless BB 37g monti cap tank for several months awhile back. It was great. No fish to feed, but there still seemed to seemed to be some crud accumulation, I suspect because there were probably hitchhiker crabs in the rock. I also had 2-3 snails in the system. IIRC, there was also a bit of film algae on the glass, so we still did weekly maintenance on the tank. For good coral growth, alk, Ca and Mg all have to be maintained, though I'm sure you're aware of that :)

Here's a pic:

http://www.lostmymarblz.com/37g-may-2005-2.jpg

vanreefer
09-15-2006, 07:06 PM
I can't remember where I read it but I think it was on Anthony Calfo's forum on RF he stated that the corals actually use the fish waste as a food source....

danny zubot
09-15-2006, 07:43 PM
So the physical waste is benificial to the corals. But the by-product, namely disolved waste that breaks down into NO3 is not benifical. Interesting.

SeaHorse_Fanatic
09-15-2006, 07:47 PM
I think several researchers are now stating that corals actually get a fair percentage of their energy needs from food (as opposed to just light) so if you go fishless, feeding your corals would still be a good idea. SPS - maybe bbs or reefroids. Clams - phytoplankton. Corals with larger feeding tentacles usually need meatier fare, like mysis.

However, I would love to set up an experiment with identical lights & conditions & have one tank with feeding & the other without. Has anybody read any writeups on a similar expt?

Ruth, let us know what you end up doing & what are the results.

Anthony

SeaHorse_Fanatic
09-15-2006, 07:54 PM
Danny,

It may not be that NO3 is totally unbeneficial for corals, just that above a very low level it becomes harmful rather than helpful. In other words, the corals may use NO3 at low concentrations, but since the oceans are usually NO3 free since different organisms like macro algae & phytoplankton use it up, corals are not adapted to thrive in high NO3 environments. My softies, for instance, seem to do better when the water is not completely nutrient-free.

Anthony

Ruth
09-15-2006, 08:06 PM
What I may actually do is to go totally fishless for say 6 months or so - evaluate how things look, growth etc. and then perhaps introduce an anemone. The anemone would of course be fed and would presumably produce waste.
If I am not getting the results I may then just add say 3 or 5 firefish (it's a 100g system with probably an additional 25g in the sump). So far all that is in there are 1 lonely SPS , 2 Crocea clams that are smiling and happy and probably 25 or so snails. Calcium reactor will be hooked up this weekend so maintaining ca/alk/magnesium will be taken care of (I add mag. chips to my reactor which seems to work to keep my mag. levels about 1450) Should be interesting. I am going to continue to feed the tank with Phytofeast for the clams probably 2 times a week or so.

marie
09-15-2006, 09:11 PM
I live by the motto "If it has a mouth, feed it".There must be some reason that corals grow so many mouths :razz:


I don't think a coral could live in a completely nutrient free enviroment, the algae that lives in it's tissues need the same nutrients that nuisance algae needs if nothing else

Farrmanchu
09-15-2006, 09:14 PM
I've read that Clams feed on Ammonia to some extent. Would be cool to have just Corals and Clams, and feed Phyto.

Ruth
09-15-2006, 09:51 PM
Well I am not planning on having any LPS or softies in this tank - we'll see how that goes as I am a sucker for ricordia and colourful LPS. I am only going to go with SPS coral and clams for now. I will feed the tank with Phyto and probably also use some Pohl's coral vitalizer once I get a few more SPS in there.

Quagmire
09-15-2006, 11:47 PM
I saw an article about feeding corals a few months back.They did a small test with 2 tanks,one with just light and one with light and food.Added a number of differant corals,then compared the differance after I can't remember how long.Huge differance in growth rates in the fed tank.I'll see if I can find it and I'll post a link to it.But it leads one to think that a tank with coral friendly fish would be the way to go.You feed the fish,the corals eat too,then eat again when the fish take their morning constitutional.

Farrmanchu
09-16-2006, 06:23 AM
Yeah, my Clowns crap right in the mouths of my LPSs. The hosting causes the LPS to shrink, but if the Clown moves on, the growth from the crapolla is apparent when the LPS expands.

albert_dao
09-16-2006, 06:34 AM
Nitrate and Phosphates are actually required for proper growth of many animals. In fact, there's European nitrate products available for people who can't keep up to the nitrate needs of their giant clams.

Ruth
09-16-2006, 02:46 PM
Will the Phyto feast not break down and create some nitrate?

albert_dao
09-16-2006, 03:52 PM
It probably will. It all depends on what your filtration is like, how many animals eat it, and how much Phyto Feast you use.