Macropodus fry

The Macropodus nest was in a difficult place to see easily, so it was hard to see if there were eggs, but after a few days I started seeing the fry. Today there are 30-40 fry (maybe more) on the glass below the nest. Now I have the great challenge - do I feed them? I don't want to - I have more Macropodus than I know what to do with. On the other hand, I don't feel comfortable with the idea of just letting them starve to death (letting them get eaten doesn't upset me, but letting them starve does, for whatever reason.

The other issue is algal growth. An awful lot of algae has grown along the glass in the tank - mostly along the right side (where the light is) especially along the back (which is against the window). I'm also getting algal growth (maybe cyanobacteria) along some of the gravel. On one hand, since my main interest is plant growth, this should not be a bad thing. On the other hand, the algae can overgrow the plants. One solution might be more plants, another is to get some more Otocinclus (since I only have one in the main tank, they could move over once they have acclimated and knocked the algae back a bit).

Macropodus: The Next Generation

To serve as a nitrogen source (and create some circulation in the plant tank), I added a few of the baby Macropodus from the breeding tank. A quick pass netted four fish - the largest one, a male, and three smaller ones that appear to have been females. Once he realised that he was the biggest male in the tank, the male Macropodus got to work nest-building and displaying at the females. On Saturday, after less than a week in the tank, he had a fairly large nest. Over the course of the evening he and the largest female have started mating. Although they are still rather small, they appear to be successfully producing eggs - perhaps 3-5 of them are visible floating around after most of their "rolls". While for rather obvious reasons I don't want any more Macropodus (I still have about 30 of them in the breeding tank), it's still pretty cool to see the fish you bred breed.

On a more focussed note, the plants seem to be growing quite well. The light intensity is high enough (at least on one end to the tank) to produce reddish foliage. There has also been noticeable growth over the last week. It really suggests that what I need most in the main tank is better lighting.

New tank

After getting home from Michigan I launched into the big clean up - two major water changes in the main tank, addition of some rocks, and the addition of a lot of new plants. I also changed one of the bulbs in the "breeding" tank to a compact fluorescent bulb, since the original bulb had blown.

When I went to Petsmart to look at plants I realised that they had fairly cheap 10 gallon tanks (sans heater, pump, lights, or lid). Since I was already thinking about setting up something to try to revive all the uprooted plants in the main tank (that had taken to a floating existence), it seemed like a really good idea. So I bought a 10 gallon tank.

Since I was only planning to use the tank for plants, I figured I could use a soil base. Unfortunately, without thinking too much I used potting soil. Bad idea. It turned out that potting soil is (a) not soil (it's wood chips and compost), and (b) it floats. So that didn't work too well. I later read that if you use soil, you need to add about an inch of gravel above it (and, I suppose, make sure the gravel layer isn't disturbed when you add the water). Anyway, I ended up getting some aquatic plant "soil" from Home Depot - it's porous, fired clay. Hopefully it will do the job of a rooting medium.

Once I established the tank I realised that it needed a nitrogen source (fish waste) so I eventually added a few "baby" Macropodus. Since they are air breathers, I figure the lack of circulation shouldn't bother them. Now I just have to ensure adequate light and CO₂ - not the easiest tasks in the world.

Butterfly (or Skipper)

A slightly out-of-focus lepidopteran that posed for a picture at church (Floyd says it's probably a skipper)

Picky eaters

My angels, which started out as tiny little things, have grown into quite large fish - probably over 4" long counting the main part of the tail. I have these sinking pellets for the corys which the angels have taken a liking to - they swallow them whole if then intercept them on the way down. So, thinking that they could use some larger food, I bought them some floating "cichlid pellets". And the angels are totally uninterested in them. When I throw the pellets in, the platies go for them (but can't do much with them) and once they soak a bit the "baby" Macropodus will eat them...but the angels seem uninterested.

Still there

It would appear that I still have fish!

I finally cleaned the tank for the first time in far too long and it appears that I still have most of my fish. There's only one Otocinclus left, but I hadn't seen any for weeks. And I think one of the baby Macropodus didn't make it.

Cleaning and a water change (and more importantly, addition of new water) has brought the tank to life. The platies are going crazy. Amazingly, in a tank full of semi-aggressive fish (seven Macropodus in there right now) it's the platies that are doing the most fighting. One of the "younger" males seems to be challenging the largest of the "older" males for dominance. Fresh water always brings platies to life - not that the males don't harass the females all the time anyway.

I'm really not sure what the deal is with the female platies. I have yet to see any more babies, but in the current set-up, I doubt they would survive (the Macropodus and the angels are good hunters, and there are just too many of them). While I was convinced that I had never seen any of the females get any slimmer, I am no longer able to say that definitively. I just didn't pay enough attention to them for a length of time - and some of them don't seem as fat as they used to be. One of them has gotten huge.

Updates

I haven't said much in a while. The main news:

* The Macropodus fry continue to grow quite well. I have introduced the two largest ones into the main tank a couple weeks ago, and three smaller ones a few days ago. The first two babies that I introduced have grown well - the larger one was almost as big as the smallest platy when it was first introduced into the tank - it's grown quite a bit since. Two of the new ones are doing ok, but I haven't seen the third one (which was smaller) - it' s possible that it's still hidden in the floating vegetation, it's also possible that it didn't make it.

* The male fighter, which was unwell since the start of the Ich outbreak died a couple weeks ago. He seemed to have swim bladder problems, and they got worse to the point where he could not stay afloat. Eventually we found some medicated food, and we fed it to him for a few days. By the second day he was looking fine, able to swim normally again. The day after he was dead.

* The female platies continue to get fatter. They look terribly pregnant, but there's no way (even given the strange breeding habits of live bearers) that they could still be pregnant after all this time.

* The adult Macropodus laid eggs every weekend for four weeks straight. The eggs hatched after about 24 hours every time, except the last time, when (after I turned the temperature down) they took a little longer to hatch. None of the batches of fry made it very far - the first one was eaten by the male Macropodus, the last two were eaten by the Angels once the Macropodus began to do a less good job of protecting the fry. They have continued to make a show of considering mating, but his attempts at nest-building have been pretty half-hearted.

* After staying small for a few months, the black Angel has done a lot of catching up, and while it is still smaller than the rest of its cohort, the size difference is no longer so striking.

Mushrooms

Just east of the bus stop there was a tree that they took out early in the Fall. After some rainy weather, there was a burst of mushrooms which seem to map out the roots of the now-removed tree.

South from George Lynn Cross

New pictures

Actually they're about a week or two old, but I just downloaded them from the camera. I also went back to some of the older postings and added pictures. The largest of the angels with three of the "baby" platies (now all grown up).

Two of the original corys (sold to me as Corydoras aeneus, but clearly some other species).

One of these non-aeneus corys, with what I believe to be a true C. aeneus and a Panda cory (C. panda).

Fry update

There are quite a few Macropodus fry around - most of them are clinging to floating vegetation, but there are a few free-swimming individuals. That raises a question - are two-day-old fry going to be doing any swimming, or are these a mixture of newborns and 10-day-old fry? After I saw the male Macropodus eat most of the fry, I assumed that there were none left. While that still seems more probable to me, it's also possible that there were survivors of the original batch. I'd say "we'll see", but no, not really - the odds of many fry surviving in the community tank is pretty slim, and even if they do, the radically different growth rates that I saw among the first batch of fry make it impossible to connect size with age.

Empty nest?

Looks like the Macropodus nest is empty. I didn't see anything in there this morning. Linz mentioned that the male didn't seem to be doing a very good job of keeping the eggs in the nest either. Oddly, he still seems to be defending the nest.

Update: Turns out that I was wrong - there were actually quite a few fry in the nest. So will the male Macropodus eat the fry tomorrow? Should I leave the lights on tonight, so that he doesn't have to gather up so many fry (and end up "forgetting" to return them to the nest like last time), or should I switch the lights off and maybe give a few of the fry a chance to escape into the vegetation, which is now considerably more dense than it was last weekend (thanks to the plants I got from Bob)?

Update II: As of Monday morning, there are still quite a few fry around. Most of them have left the remnants of the nest and are on the underside of a large Echinodorus leaf that's floating on the surface of the tank. While the male Macropodus was still defending his portion of the tank, I couldn't tell if he was doing anything to "manage" the babies.

Macropodus fry

The first batch of fry are doing well, but the size disparity is getting larger. Most of the fry are "average" size - around 6 mm long. Several are smaller than average - around 4 mm long. And some are much larger than usual - over 10 mm long. [Update: The large ones are over 14 mm long]

It's the giants that are really interesting. Not only are they about twice the length of average fry, they are also 4 or 5 times the overall size of the average fry. At least one of them appears to be an air-breather (the labyrinth organ doesn't develop until the fry reach a certain size).

I'm interested in what the evolutionary strategy is here - or whether there is one. Floyd asked the question of whether there is some sort of advantage to having some fry remain stunted - perhaps as a food source for their larger siblings. While that might explain the smallest ones, it really doesn't explain the very large ones. There's a continuum of body sizes, but the very large fry seem to be outliers.

I have no idea whether this is typical or not. It's possible that these are truly unusual individuals, but it's also possible that this is a normal strategy for Macropodus. If so, it makes me wonder whether this could be viewed from the perspective of asynchronous germination in seeds. The normal way to interpret this would be as some sort of scramble competition - that the most successful strategy is to get big as quickly as possible, because faster growth allows you to outcompete your siblings and escape many predators (including your parents).

The problem with this interpretation is that getting big probably isn't a winning strategy for a territorial species living in a limited environment. Chances are, not only is reproduction only an issue for a fish that can claim a territory, it's also likely that reaching adult size is only an option if a territory becomes open (much like a tree colonising a gap). If that is the case, then growing large quickly doesn't guarantee success - it only represents one out of a range of strategies. It may be that some fish get big quickly to occupy an immediately available territory (if one exists) while other mature more slowly, with the "objective" of staying to occupy a territory that becomes available later on.

Another batch of eggs

The Macropodus laid another set of eggs last night. I don't have anywhere to put the fry, so I suppose they will also live a short life.

Macropodus fry

While the second batch of fry succumbed to parental cannibalism, the older ones are doing well. My brine shrimp yields have been pretty good, so they have been eating fairly well. What's remarkable is the differences in growth rate among them. There are several fry that are considerably smaller than the average, and there are a couple that are considerably larger than average - most notably, one giant who is 2-3 times the size of its siblings.

I ran the filter for a little while again yesterday - although the fry were still using the entire water column, I was a little concerned about oxygenation and BOD (biological oxygen demand). The fry are unlikely to be air breathers yet, and there's sure to be other decomposable material in the water. Added oxygen is also going to benefit the bacteria involved in nitrogen cycling (which are mostly aerobes). Still, I don't like the leave it running too long, since the fry aren't yet strong enough swimmers to deal with the water currents set up by the filter.

So while still water is likely to reduce the energy demands of the fry, it also reduces the oxygen content of the water (and possibly the ammonia and nitrite concentrations). I don't know if it's a net benefit or cost. On the other hand, the Ludwigia seem happy with the stillness and the falling water levels. Several stems have emerged above the water level, and at least one of them has flowered. The breeding aquarium has taken on something of a pond appearance, which I really like.

Infanticide

I decided that leaving the light on overnight (as I did on Friday night) probably wasn't the best idea (if nothing else, I probably didn't sleep as well with the light on), so I turned it off Saturday night. On Sunday morning when I turned the lights on, the babies had scattered quite a bit. The male Macropodus diligently started gathering them up and bringing them back to the nest, but af some point he stopped spitting them back into the nest. He then went to the nest and started gather those ones up as well.

A few hours later there were still a number of them left, but my this morning I couldn't see anything left of the second batch of baby Macropodus.

Day 3

I left the light on in half the tank tonight, to make it easier for the Macropodus to keep track of the babies. As soon as I switched off the light in the other half of the tank, all of the platies (and several of the angels) moved into the lit half of the tank, brining them into what the consider their territory. That said, most of the platies ended up in the deep water below the nest, which the Macropodus ignore.

The nest is full of fry. Not sure what happens next - they are supposed to be free swimming by day 3. I'm not sure what happens then - if he will still protect them, and if he will be able to protect them.

Hatching

Overnight, with the lights out, the male Macropodus appears to have done little nest maintenance, such that when I put on the lights this morning there were eggs and babies all over. Since then he has been diligently collecting babies and eggs, while chasing everyone else away from the area of the nest. In this he has had the assistance of the female. Between the two of them they have claimed about half the surface area of the tank and maybe a third of the total water volume (they aren't bothered by fish more than about a foot under the nest).

While the male seems to have a good grasp on his role, the female seems a bit less sure what to do. Unlike him, she is still eating - may be eating eggs and fry as well (I have seen her gather up errant fry, but I haven't seen her return anything to the nest). In addition, the male chases her when she gets too close to the nest. On the other hand, she is doing a good job chasing everyone else away from the nest. She seems to have an especial dislike for the angels - she goes to the far end of the tank to find angels to chase.

I noticed that the fry tend to attach to surfaces - not just bubbles, but also the glass or plant stems. I suppose there's survival value in that - they are less visible if they attack to vegetation.

Macropodus nest

The nest is built under and around an Echinodorus leaf that's right on the surface of the water. The male is being an attentive father, although he leaves the nest to chase the female every now and again. I'm not sure if he still wants to mate, or if he is keeping her away from the eggs.

The female, on the other hand, is behaving oddly - she has taken to chasing the angels, which is interesting, since the larger angels are about her size. She ignores the smaller fish, but seems determined to keep the angels out of the portion of the tank that includes the nest. The male, on the other hand, seems to ignore the angels pretty much, but chases any platies that get too close.
A shot of the nest through the side of the tank (and a nice shot of the camera, reflecting off the glass)

These are taken from above. The eggs are visible in the lower picture.
And here's the male Macropodus, sitting below the nest. No longer in breeding colours, he seems pretty washed out.

Back at it again

Less than two weeks after the bred, the Macropodus look like the want to breed again. The male has built a nest, and the female is hanging around it in a fairly interested fashion. If they do breed again, I don't have anywhere to move them - I just don't have another tank. Sadly, the eggs will probably end up as fish food. I'm more worried about how the male will react - he's likely to go crazy trying to defend his nest, and may actually hurt some of the other fish (he is, after all, easily the largest and most aggressive fish in the tank).

Well...we'll see what happens.

Update: Turns out that events had overtaken me - he already has a nest full of eggs. They must have mated last night. Surprisingly, he seems to have done a pretty good job of defending the nest - it hasn't turned into a free-for-all feeding place.