The Fishless Reef Tank...

[Avalon_Princess]

I have been using the search feature but this doesn't seem to be a widely discussed topic, mainly the posts I could find were a member asking a question regarding this which is never completely answered.

Although i do understand aesthetics are a big part of this, would it be possible to look more at the mechanical/physical nature of keeping a fishless tank rather then simply stating fish look nicer?

So what are peoples opinions on the concept of keeping a reef tank entirely without fish? Would it make feeding the corals harder? Cause paler colours and other problems? Would it lead to an eventual crash?

I know some people have kept fishless tanks out of necessity pico tanks and small nanos are often without fish as are frag and propagation tanks but it just seems and aspect of reefkeeping that is often ignored.

So opinions? further information?

 

[chrisstie]

Honestly, I don't think you'd see a change if you fed your corals well.

 

[KarlBob]

I've seen people claiming that fish are important to coral health, but I can't recall all the reasons.

Hopefully they'll complete the migration to the new software soon, and we'll have a better-working search feature. That, or we'll lose the last 2 years of posts!

 

[robexcoral]

im getting rid of most my fish the fish were raising my nitrates to high

 

[108reefer]

other than stating the obvious - that fish and coral reefs have some sort of symbiotic relationship (you don't ever see a natural reef without fish). I don't know the scientific reasoning behind it. I am pretty sure from readings - it is a nutrient "thing". not a great response - just looking to nature.

 

[sunny1977]

one of my friend has kept sps tank 120 gal without fish for a year and i have kept mixed reef with one fish for 2 years with no problem at all . Even i dont even have skimmer only on miracle mud and refugium, things are easy i have to say but after couple of years your tank gets very boring

 

[suta4242]

Re: The Fishless Reef Tank...

<a href=showthread.php?s=&postid=15310517#post15310517 target=_blank>Originally posted</a> by Avalon_Princess

So what are peoples opinions on the concept of keeping a reef tank entirely without fish? Would it make feeding the corals harder? Cause paler colours and other problems? Would it lead to an eventual crash?

Not sure that I understand your question. So excuse me if I ramble... But I don't believe you need fish waste to feed corals, except possibly in a nutrient poor acro tank running a grossly oversized skimmer. You could always spot feed where needed eg for certain LPS.

That aside I see many benefits in having a fishless tank. In my cube I waited 3+ months after cycling to put the first fish in. That tank was teeming with worms, feather dusters, tunicates, pods of all sorts swarming through the water and sides of the glass.... worms that would rise from the sand to feed on barely visible microalgae that grew on the glass. :inlove: And that was during the day! Also the larvae from all this life would have provided nutrition for some of the corals.

Then the first fish came - a voracious flame angel. Within a few months that tank looked like a barren wasteland. :eek2: Don't get me wrong, I wouldn't trade the fink in for anything. But he's not going into a bigger tank I'm setting up. :celeb2:

I think we often call ourselves reefkeepers, but by and large we're coral and fish keepers. A tank devoid of fish would have a much greater biodiversity and function better than one with fish. However, there are plenty of popular inverts such as hermit crabs and ornamental shrimp that are on par with fish when it comes to changing the landscape of a reef tank. So you'd have to be careful if you went fishless but kept them. Each to his own I guess.

 

[ctenophors rule]

i realy like the fishless look for the same reason listed by suta.

a lot of people say that aquariums become boring, but that is only because it is always the same.

if your biodivesity is kept high, by having as few aggresive predators as possible, for exapmple, just corals and live rock, you would never be bored. (assuming you started with good high quality uncured live rock, and a mondo skimmer, like the one i am moking for 20 bucks! build thread on the way. lol)

just my .02, anyway.

oh, and the nutrient benefit? thgat makes no sense to me. in a system without fish, wouldn't the population of organisms eventualy rise to a level that would support the symbiodinium zooxanthellae?

also, i believe that nutreints can easily be supplemented.

and as anyone with more than 100 posts under their belt should know, the main problem people have with tanks are nutrient levels that are tooo high, not toooo low.

i think you will be pleasently surprised if yo uset up a properly cycled tank fishless reef, and i know that if you aren't, you can always adfd fish later.

enjoy, sorrry i typed to long, but you know, when i type it is like i am having an internal monolouge, and i feel a lot like jd from scrubs.....is that wierd?

 

[Avalon_Princess]

When I searched for information on reef tanks running without fish (and had to trawl through 90+ pages of threads predominately about ich infested tanks) the one comment that turned up a lot was that a fishless tank would be too sterile, the corals would take on pastel colours and eventually crash. It didn't make much sense to me but I'd count myself still at the starting out stage so figured a thread with quality information would come in useful.

I'm planning in a fishless tank for a few reasons, I move to university early next year and from them on my tank will probably be routinely broken and down and set up as I move around. I'll also have to downgrade due to volume restrictions. I've also never been big on fish I managed to run a four foot FW planted tropical tank for twelve months without ever stocking it before as I never saw anything I liked LOL.

The rock I have is incredibly alive, almost too alive by all counts considering the 'baddies' I ended up with but it does seem a pity to add fish and watch it all disappear.

So a fishless tank would most likely be easier to keep then a reef with fish?

This is what I believe would occur with a fishless reef, please correct if I'm wrong!

From what I can tell a fishless reef would be much closer to the set and forget tanks some reef owners strive for. With the appropriate selection of corals you wouldn't need a skimmer as the DOC's that did exist would go straight to feeding the corals. There would be a greater diversity of life so you would be more likely to have the creatures needed to fill each ecological niche within the aquarium. Feeding could be cut down dramatically once again depending on coral selection but if you stuck with the corals that depend predominately on photosynthesis you'd probably only need to add small amounts of food every couple of weeks to ensure everything remains well fed and happy. You'd also be free of worries about ich and other illnesses that require harmful medications as treatment.

A fishless tank would be able to run successfully with much less of the external paraphernalia associated with keeping a reef. A refugium would be obsolete as the tank itself would act as one. Filters would have much less use without the fish waste being continually released into the tank.

Overall you'd have a tank that would be much lower nutrient and also have a slightly large 'buffer zone' in the case of a crash or a toxin being released into the tank.


The tank I'm working on at the moment is predominately softy dominated (my Mum snuck a favites coral in LOL), with an overpowered skimmer (ctenophers rule- can beat you my skimmer was only $10 works like a charm too LOl) and approximately 25 x turn over. 10.4 kg of Liverock on a barebottom. So far it's been up for a bit over two weeks and the biological diversity is amazing I've seen so many different critters, huge feather dusters, rather a lot of crabs a large variety of worms, different types of algae and hundreds of species of sponges and tunicates.

 

[KarlBob]

<a href=showthread.php?s=&postid=15322592#post15322592 target=_blank>Originally posted</a> by Avalon_Princess
With the appropriate selection of corals you wouldn't need a skimmer as the DOC's that did exist would go straight to feeding the corals...

Overall you'd have a tank that would be much lower nutrient and also have a slightly large 'buffer zone' in the case of a crash or a toxin being released into the tank.

The tank I'm working on at the moment is predominately softy dominated (my Mum snuck a favites coral in LOL).

A softy dominated tank, especially one that also contains a few hard corals, can benefit from a skimmer whether it contains fish or not. Soft corals deliberately release a lot of toxins. On the reef, they secure space and drive out competitors by emitting chemical warfare agents. In the reef tank, those chemicals are removed by water changes and protein skimmers. Without a protein skimmer, they may build up to levels that harm the tank's inhabitants, particularly hard corals. In the case of nutrients, the buffer zone might be larger, but when it comes to toxins, the lack of a protein skimmer and the presence of soft corals will actually shrink the buffer.