Best Practices: Substrate observations

[bluescape]

Hi Folks, this is my first post on this forum. My professional background is in scientific and financial research. I breed and research aquaculture for hobby.

I'm hoping to tap into your collective experiences to resolve an inconsistency I have noticed. My question is regarding optimal broodstock set-ups for clownfish. I had always operated under the assumption that the various clown species would spawn most readily in an environment that was as “natural” as possible while containing minimal distractions/threats (i.e. other tank mates).

My assumption was that certain ‘easy breeders’ (i.e. ocellaris, percs, etc.) were typically housed in bare bottom tanks simply because this alleviated maintenance man-hours and expense. I assumed that professional breeders utilized BB tanks for their broodstock because this was more efficient and the fish would tolerate it, not because the fish preferred BBs. This assumption was supported by anecdotal evidence – difficult clown species (i.e. Latz) seemed to spawn almost exclusively in large, full-reef systems whereas hardy species spawned in both BBs and full-reef systems. Additionally, Hoff suggested that more difficult species could be “settled down” by placing substrate in their tanks.

Therefore, I was surprised to read in Wittenrich’s most recent book ‘The Complete Illustrated Breeder’s Guide To Marine Aquarium Fishes” that he believes clownfish breed more readily in bare bottom tanks. Congruent with Wittenrich’s observations, I have seen a few posts on various message boards from seasoned breeders who have suggested that pairs of reluctant fish spawned shortly after gravel was removed from their tanks and others stating that their fish seem to prefer bare bottom set-ups.

I have a hypothesis on this, but I wanted to gather as much information as possible. Do most breeders on this forum utilize BB tanks for their clownfish brood tanks? Do you have any evidence (anecdotal or otherwise) that suggests certain species prefer BB vs. tanks w/substrate? Do any members here breed clownfish successfully in broodstock tanks with traditional aragonite substrate (I am particularly curious about aragonite substrate due to its relatively high reflectivity index, does anyone here successfully use aragonite?)

I have seen this topic touched upon, but my goal is to compile enough data to reach a somewhat definitive conclusion. I'd appreciate any input or experiences you can share regarding this issue.

Best Regards,
Mark

[Kmiec123]

Hi Mark, and Welcome to MOFIB!!!!

I have a bare bottom brood stock system at present. I was just actually considering adding some substrate to the larger (20 gal.) tanks in the system with some live rock to give the system more filtering capability. What types of substrate do people use? That is a good questions. I have always used aragonite, but what partial size is another good question. I use the sugar size in my reef tanks. I do have 4-40 lbs. bags of a courser material I was going to use.

What part of the US are you from, you profile don't show? I would be more than willing to help would with some observations or testing if you are interested, just let me know the protocol you are looking for.

[bluescape]

Carl,
Thanks for the warm welcome! I am based in Chicago, Illinois (sadly I’m seldom in Chicago as I travel for work, but that is technically where my “home” is).

I see that 36 people have viewed this topic, assuming that 33% have successfully breed clownfish and netting out myself, we only have an 8% participation rate. Based on this low net participation rate, I’m guessing that this question has already definitively been answered somewhere else. I will poke around some more and circle back.

Thanks –Mark

[Scottt]

I don't know of any true scientific experiments done on this topic. Easy breeders breed anywhere. Clowns actually prefer flower pots over an anemone in many cases (so natural is not necessary). My clowns breed in a bare bottom. However, many people around me have clowns which breed in their aragonite bottomed displays. In my opinion, the substrate doesn't matter. A bare bottom facilitates cleaning, increasing water quality. So most breeding minded people do that.

[bluescape]

Scott,

Thanks for your response. Do you or does anyone you know breed some of the more delicate species in BB tanks? (ex. Latz, McCs, etc?)

I think Matt W.’s observation that clown’s seem to breed MORE readily in BB tanks is very peculiar and seems inconsistent with the fact that most people I know who breed delicate species, do so in full reef type set-ups.

Possible explanations for the seeming inconsistency:
1.Matt W. was referring primarily to the more common clown species. Many specimens of these species (Ocell, Percs , etc) were captive bred/raised in BB tanks, so to them a BB tank is more ‘natural’.
2.Bare tanks make fish initially less secure, but in the long run a sparse tank “forces” fish to get more thoroughly acclimated to their caretaker and surroundings, and therefore they end up being more tame (and calm).

-Mark

[Scottt]

I don't know anyone who does the delicate species. However, your hypotheses seem good to me. I'm interested to see the outcome of this question, as i'd like to try some of those species in the future.

[Kmiec123]

I'm starting to add some Sand today, I'll keep you posted.

[bluescape]

Thanks Carl.

I'm setting up a tank as well w/aragonite. (Side note, I had to take a break from my marine hobby due to school/work, this will be my first tank in years!)

[Rook]

I know someone who places a thin layer of sand on the bottom of the broodstock tanks. The reasoning...eliminating the need to scrap algae off the bottom. Seems to be a very constructive purpose. The clowns are regular breeders so it seems to have no negative effect.

[bluescape]

Thanks Rook.

[Clownfish75]

Hi

I only just read this thread, but you do propose some interesting ideas, but also present some big problems.

Most of my pairs of clownfish spawn in bare bottom tanks, why because then i dont have issues cleaning the sand, basically its easier to suck up the crud this way.

I seriously doubt that the presence of or absense of a substrate will influence the spawning of any given pair of clownfish.
I agree that the presence of things to settle clownfish would help induce spawning, as Hoff indicated in his book, but i would be more inclined to say it is an anemone than substrate.

As an example, some people might suggest that a black ocellaris or a nigripes are difficult spawners, but i cant get them to stop most of the time, and thats with no substrate.

Thinking from an ecological perspective i think you will find that many anemones, specifically, Magnifica and bubble anemones are on reef structures large distances from any sand based substrate. Given the size of a clownfish home range, which would have to be lucky to exceed a couple of square meters, I suspect many occur well away from sand.

Im not saying your wrong far from it, we as a group need more people to think outside the box or fish tank, otherwise we keep perpetuating the same mistaken theories.

what i am suggesting is that would it not be more likely that an anemone would play more of a role to reduce stress and therefore increase the likely hood of spawning?

Christian

[Kmiec123]

bluescape, Added sand in three 20 gal. tall tanks on my broodstock system. No ill effects at this point. The pairs have not missed a beat in spawning...they seem to care less. I did consider adding individual species of clean up crew in each tanks....Some Blue leg hermit crabs in one, Scarlet's in another, and red legs in in last....Then if I ever got larva I would know what species.