Greenbanded Gobies - Take 2

[mwp]

Hurah! Another spawn of our "mystery" larvae has appeared...granted a couple days "late" but who cares! A much larger batch, roughly 150?

So I've considered our experience the first time around and made some adjustments. First, all larvae are in one large specimen container (roughly 1/2 gallon). I harvested 1/3 gallon from a rotifer culture (that's at a density of roughly 50-100 per ml, L-Strain), sieved it and fed it in (again, lots of those copepods went in as well). As my phyto cultures are not yet up to snuff, I added enough Phytoplankton (this time Liquid Life's) to turn the water ever so slightly green.

The other change I've made is that an airline is already in place, bubbling about 5 bubbles per second. It's enough to keep the water moving slowly...just a touch more movement than I use in my rotifer cultures.

Anyone have any different ideas at this point? I'm hoping to make it past 24 hours this time. Someone suggested adding a small amount of carbon which I think I'm going to do as well.

The only other thing I can say at the moment is that I pulled one out and looked at it under the 10X loop...didn't see it eat anything and it sure looks "SKINNY" already, i.e. sunken belly, and that's on a newly hatched fish! There are definitely NO yolk sacks on these guys, so instant feeding is likely a must! It LOOKS as though they *might* be feeding, but honestly, I haven't seen any "S" curve-type striking.....

Thoughts?

Matt

 

[mwp]

One more comment, I left about a dozen in a net breeding with the female mandarin we're "training" to take frozen foods (it's working quite well). These larvae seem entirely too fast for her as well as really not having quite the right movement (all she's eating now is frozen enriched brine )

At least this way, if the large batch in the specimen cup keels and we still have live ones in the net breeder, we'll have a better idea that it's a water quality issue!

Matt

 

[mwp]

Quick update. Things were not looking good this morning and are continuing today to look subpar.

A water test revealed a slightly elevated nitrite level (0.25 or so) - 50% of the culture water was changed and 2 drops of Prime added. The rotifer population was definitely "down" a bit, so I added some more. Also added around 10 ML from a Nannochloris culture that's coming on strong (only started it this past weekend). Also added some Caulerpa springs to help maintain good water quality.

With that said, it's looking like this is going to go down just like the last one...all DOA in 24 hours or so...at least that's where it looks to be headed.

I'm not at the point yet where I can follow the recommended steps of doing a 10 gallon tank, painted sides, adding 1 L of Isocrysis per day (in fact, that culture seems like it's not starting from the disk I used...). We're simply not at that point yet.

Knowing how this has all gone down, I also know to expect a small secondary hatch tonight (if we follow the pattern of the first time around). I'll get some more babies to work with in another, small specimen cup. What if anything should I try to change to increase my chances?

MP

 

[LotR Clown]

I don't know if it is normal for larvae of this species to be extremely thin upon hatching, but if it is not normal, your problems getting past 24hours could be related to the nutrition of the broodstock.

 

[mwp]

Well, hmm. A lot of speciulation has gone around "nutrition" of the broodstock in this tank. I *think* we've ruled it out but I'll run down the list.

Feeds include:

- Hikari Frozen Brine (enriched)
- Hikari Frozen Mysis (enriched)
- San Francisco Brine (enriched)
- Cyclopeze
- new to the list, SOME of the fish are taking Formula One
- occasional live baby brine or adult brine, both usually enriched
- rare feedings of live copepods (Tiggerpods)

Also, I've been soaking most all of the frozen brine / mysis in Selcon.

This tank receives "saturation" feedings 3/4 times per day. In other words, the fish are STUFFED with top-notch food.

24 hours in, we're at about a 75% loss - not 100%, but most of the remaining live babies are on their sides on the bottom. The larvae seem to go from VERY active at hatch to less active, to losing attitude control, to being on the bottom, swimming briefly, to finally death. Sure sounds like starvation thus far...I pulled a larvae earlier today and looked at it under the 10X loop - didn't look like there was anything in the gut. Another look this evening...still can't say they're getting ANYTHING in the way of rotifers! Let me say that in a size-comparison, it *looks* like one of these larvae taking down an L-Strain rotifer would be equivelent to a human shoving a double-quarter-pounder-with-cheese in their mouth in one gulp! In other words, the rotifers look too big.

Well, that's were we stand at 24 hours...

MP

 

[NicoleC]

A few other items for thought:

1) The broodstock are too young or inexperienced and not producing healthy eggs/larvae yet
2) The eggs are hatching too late, so the yolk sac is gone
3) Broodstock parasite load, which are producing weak larvae who may be affect by parasites themselves.

I am not terribly impressed by the food list. It's not bad, but neither is it stellar. The fat content is very high, which is not bad except that it might be squeezing out protein.

The addition of F1 sounds like a good move, and I would add F2 to the mix -- both frozen, not flake or pellets. I'd skip the brine altogether and feed more variety, like table shrimp, clams, mussels, squid, etc.

To make variety easier, get some fresh seafood, soft freeze it then chop it up in the food processor to goby size. Mix in as desired CE, spirulina, vitamins, etc. Spread over eggcrate or frozen fish food trays and freeze, then pop out the cubes, package and seal them up and you have convenient variety food you can mix in with the prepared diets.

 

[mwp]

Nicole, I must admit a strong curiousity regarding your repeated citations of parasite load in broodstock fish. Has this been a problem you've encountered in the past?

Regarding your specific points.

1. VERY possible, as this is the 2nd spawning.
2. Again, possible. However, looking at photographs of newly hatched Neon Goby larvae, ours pretty much look identical. Same shape and all. I *think* we're getting healthy larvae.
3. The pair of GBGs are captive-bred / tank-raised, so your concerns over the common "parasite load" of wild fish in this case seems highly unlikely.

When it comes to the GBGs, we are looking at micropredators who have a system full of live rock and macroalgae at their disposal as well. I have no doubt they take down some naturally occuring live foods as well as all the above.

While I can concede that there is a possibility that diet *could* be an issue, especially with the many failed spawnings of the cardinalfish, I'm still not convinced that's what the problem is. Afterall, I'm breaking like 15 other "rules" in this "orgy tank" as it is LOL!

MP

 

[NicoleC]

The fact that a fish is CB means zip, zero, nada when is comes to parasites unless they are housed in a dedicated system where everything has been QT'd and one is careful not to splash, use tools from another tank, and always sterilize hands moving from one tank to the other, etc.

CB fish are not immune to parasites, they are just less likely to have them when they leave the breeder. If the fish came from a LFS and was in the main system, they were exposed to numerous pathogens. If the fish was introduced to a tank with other un'QT'd fish, they were exposed. And so forth.

I've heard every excuse you can imagine for not "bothering" with QT, most of which revolve around laziness. I've also had many of those people at my house late at night getting medicine, fish trapping advice and borrowing a hostpital setup for their sick fish.

Many people also get away with it. They have fish that are chronically burdened and live shorter lifespans, but there is no major disaster. They are not expecting their fish to spawn regularly and have healthy children, though.

My clownfish pair was the initial fish in my current system. I had not yet learned harsh lessons about deworming fish as a regular protocol and they were CB and showed not signs of illness in QT. In the tank they went, grew well and looked fat and healthy.

Years later, I had a parasite get through QT undetected and unkilled by standard parasite treatments. I pulled all the fish, treated with praziquantel and hyposalinity.

When I returned the clowns to their tank, I was rewarded with double nest sizes! They have been routinely laying bigger and healthier nests every since, and the female has packed on some additional size.

These were healthy, vibrant, CB fish.

Hyposalinity costs nothing and Pipzine is cheap, and it can help bring your broodstock to peak health.

 

[mwp]

Nicole, while I'm not discounting your experience, I have to protest that wild fish, even with their potential "parasite load", are able to reproduce just fine. Healthy fish are, to a great extent, "healthy fish". Right now, my last concern is with raising brood size (which seems to be going up on it's own anyways)...my concern is with keeping the larvae alive and feeding. Unfortunately I'm the type of guy who wants hard data to back up something like a profolactic treatment before I'm actually going to implement it (and as I've stated before, I literally do not have the space or facilities to do it here, so if/when we move, maybe, but right now, QT is simply not an option...has nothing to do with laziness but everything to do with trying to convince the significant other to set up more tanks. I have to work with what I've got )

In my years breeding freshwater, I have never profalactically treated fish for external or internal parasites and haven't had some problems. Maybe "marine" fish are just that different, requiring the absolute utmost top-notch care and treatment, or more likely, the issues I'm facing lie elsewhere (like the fact that I'm trying to place 150 goby larvae in a 1/2 gallon container).?

We're now 36 hours in, a new record of sorts, as we still have 4-5 larvae swimming around. If they've made it past the "hump" by tonight, 2 days in, I think we have a shot at making some progress. Remember, we had larvae show up at "24 hours in" on the first spawn, and they were all gone within 24 hours of isolation as well. So 48 hours, that's the mark to beat right now.

Also probably worth mentioning, no new larvae showed up last night...different than our first time around.

MP

 

[Kathy55g]

<a href=showthread.php?s=&postid=6646886#post6646886 target=_blank>Originally posted</a> by NicoleC
A few other items for thought:

1) The broodstock are too young or inexperienced and not producing healthy eggs/larvae yet
2) The eggs are hatching too late, so the yolk sac is gone
3) Broodstock parasite load, which are producing weak larvae who may be affect by parasites themselves.

I am not terribly impressed by the food list. It's not bad, but neither is it stellar. The fat content is very high, which is not bad except that it might be squeezing out protein.

The addition of F1 sounds like a good move, and I would add F2 to the mix -- both frozen, not flake or pellets. I'd skip the brine altogether and feed more variety, like table shrimp, clams, mussels, squid, etc.

To make variety easier, get some fresh seafood, soft freeze it then chop it up in the food processor to goby size. Mix in as desired CE, spirulina, vitamins, etc. Spread over eggcrate or frozen fish food trays and freeze, then pop out the cubes, package and seal them up and you have convenient variety food you can mix in with the prepared diets.

Eggcrate! Brilliant! why didn't I think of that?

 

[ediaz]

 

[NicoleC]

Nicole, while I'm not discounting your experience, I have to protest that wild fish, even with their potential "parasite load", are able to reproduce just fine. {snip} Unfortunately I'm the type of guy who wants hard data to back up something like a profolactic treatment before I'm actually going to implement it (and as I've stated before, I literally do not have the space or facilities to do it here, so if/when we move, maybe, but right now, QT is simply not an option...has nothing to do with laziness but everything to do with trying to convince the significant other to set up more tanks. I have to work with what I've got )

In my years breeding freshwater, I have never profalactically treated fish for external or internal parasites and haven't had some problems.

Wild marine fish are not sitting in their own filth. Even the best kept aquariums are very polluted compared to wild reefs. And survival rates in the wild are very, very low. That's why they have so many eggs! If a pair produces 100 eggs every month for 5 years, that's 6000 larvae. If only 2 survive to breed, mother nature calls that a success.

FW fish are usually the product of generations of captive breeding. They are therefore both better suited to aquarium life and also have been through the hands of breeders who weren't so shy about killing parasites.

 

[rsman]

well figured id stick my foot in my mouth so here I go

I think the parent food is kinda plane, nothing in its list gets me excited about such a "great food", well nurished parents not only have more eggs, but the eggs have more mass, and that *might* add to your problem.

on parasites i have little opinion except, the FW fish I raised had more parasite problems than I ever had with any SW fish. and NONE of them came from WC sources. while most of my SW fish were WC.

 

[mwp]

Well, all I can say is we've broken the 48 hour mark. The only real changes I've made from the first is the addition of carbon, immediate aeration, and definitely better feeding of the larvae (including small introductions of Nannochloris, Isocrysis and Tetraselmis). Only 4-5 remain, but we're definitely going in the right direction here. Hopefully by the time the next batch is ready, the phyto cultures will be up to speed.

Meanwhile, 2 species of cardinals are going at it this evening...I wonder which one it will be? (if either?)

MP

 

[mwp]

Well, somewhere between 48 and 60 hours the last 4 larvae kicked the bucket...just in time for the Bangaii cardinal spawn To tumble, not to tumble....

We'll probably NOT SAVE the next couple batches of goby larvae if the bangaii's are going strong. We're likely moving too, so although I may be able to finally get the go-ahead on a 10 gallon (and the phyto should be ready) I may not go that route anyways.

So - IF ANYONE IN THE CHICAGO AREA has the resources on hand and would like to come get some GBG larvae after they hatch, SHOOT ME A private message! I'd say likely sometime next week...won't know until babies start showing up again.

MP

MP