Guppy Fry Dying.

[rvijay07]

I have a tank with about 12 Guppy fry about a months old and 3 fry over 3 months. Every now and then a fry is dying in this tank. I don't know why. Sometimes, this also happened after a water change/cleaning.

However, this has been consistent. There are no adults in this tank, lots of plants. Temperature maintained well. Cleaning every two weeks. Very few fish for this tank.

What could be the reason(s) for these deaths ? At this rate, I will not have any guppy fry left a few months down the road. If they are all going to die so soon, I might perhaps as well use them as food for my Betta.

Thanks.

Vijay

 

[Zic]

OK, a few things. First off, is the tank cycled? I don't know for sure, but I would imagine that fry are more suseptable to ammonia poisoning.

Second, what are you feeding the fry? Do you actually see them eating?

Is the water you add when doing a change similar in parameters to the water in the tank. For example, the water you're adding isn't cold water, is it? Or, for <another> example, the water you're adding doesn't have a higher or lower Ph than the water in the tank, does it?

This is all I could think of off the top of my head.

 

[rvijay07]

Excellent questions. Yes, the tank is cycled. I feed the fry powdered flake food. I see them eating the food all the time. Water parameters are also consistent.

If water parameter was not correct or if the food was not being eaten, they would all have perished a long time ago. Hence, I feel it must be something else.

I have water weed that has taken over 1/4th of the tank almost. Can there be excess CO2 production or something of that nature ? There is a lot of algae in this tank due to flooding with plants.

Vijay :?

 

[Zic]

Ummm.....I'm really not sure. Sorry. I'm so lame.......................

 

[Jack]

I would try feeding something more nutritious. Brind Shrimp Direct sells fry food that will work well for your guppies. Golden Pearls (typically used for corals, but works fine for FW fry), Spirulina powder, decapsulated brine shrimp eggs, artemia, ...

Fry often require better nutrition than adults. Also, it's sometimes hard to pulverize flake into a size that small fry can eat. You are much better off going with a smaller, higher quality food.

 

[CRaZeeeBiTcHisH]

can you see any abnormality or change in behavior before they die? i have fed a zillion guppy fry powdered flake food with no problem..(put some flakes in a
baggy and pulverize it )... when you change the water , is there a strong current of water flowing in or out of the tank that could be injuring them? mine couldn't fight much of a current successfully . 8O

 

[Jack]

I'm actually raising a ton of guppies in a 75 gal. Sounds exciting doesn't it! Actually, the guppies will be food for the Belonesox that will be added soon. My tank also has a lot of current (all the time) and also has many plants, rocks, driftwood and such. I have so many guppies that I can't really give you their behaviour prior to croaking. I know some fry die (some also get into the overflow and wash down to the sump), but I always have size ranges of tiny fry to mature adult in my tank. Therefore, many make it to adulthood and the cycle continues.

A better food would likely help you to raise more fry to adulthood, but if you have med sized guppies that are dying, it is not likely the food. Have you used any bug spray, bug fogger, or any other chemical near the tank lately?

Also, do the fish seem to die at night or both night and day. An excess of CO2 could cause a sudden drop in pH if your alkalinity (carbonate hardness) is too low. This is a common problem in SW tanks. Guppies seem to like a higher pH and greater carbonate hardness. Many folks also add some salt as guppies often live in brackwater.

What about oxygenation? It appears that you have very little current in your tank. Are you getting good surface agitation? A small powerhead blowing near the surface will add much more oxygen than an air pump.

All that being said, the deaths might just be natural. For whatever reason, small fry just aren't as hearty as larger sub-adult or adult specimens. You can raise a greater percentage to adulthood if you use a better quality food and if you feed more often (most recommend feeding guppy fry several times per day). Furthermore, feeding more nutritious food and more often will make your guppies grow faster. Remember, feeding more often does not mean overfeeding. You just feed smaller portions, but more times per day.

 

[rvijay07]

Excess plants and filter turned off for days at a stretch may lead to oxygen depletion. Also, I feed in excess, insted of feeding several times daily. Perhaps the excess food rots. Most seem to die at night.

Vijay

 

[Allivymar]

Nice detective work rvijay07. You may have solved your mystery.

O2 levels fall at night in well planted tanks. If you are turning your filters off and they are your main source of surface agitation, that combined with lots of plants can be enough to lower DO (dissolved oxygen) overnight. You may want to try keeping the filter on, or adding more aeration to move that water surface. Although, why turn the filters off? Or are you just turning them off for a few mins while they feed?

And your feeding strategy doesn't help. Why one big feed instead of small frequent ones? I'm also guessing you don't vaccuum up the leftovers; that would help too.

Whats the temp of the tank? Higher temps lower O2 levels as well.

You never did mention ammonia/nitrite levels. What have they been?

While this article is more "big fish" specific, its has a nice discussion bout DO: http://edis.ifas.ufl.edu/BODY_FA002

Oh, and BTW, this is why we always bug people for info. The feeding schedule, the plants, the filters turned off, die offs at night were not mentioned initially. Heh, you may have not needed to do all that detective work had that been mentioned initially.

Good luck! Let us know what happens when you make some changes.

 

[rvijay07]

Nice detective work rvijay07. You may have solved your mystery.

O2 levels fall at night in well planted tanks. Although, why turn the filters off? Or are you just turning them off for a few mins while they feed?.

I put excess food. So, don't want the left overs caught in the filter. Hence, filter turned on, only for some time.

And your feeding strategy doesn't help. Why one big feed instead of small frequent ones? I'm also guessing you don't vaccuum up the leftovers; that would help too.

Admitting it openly, just plain lazy to feed several times daily.

Whats the temp of the tank? Higher temps lower O2 levels as well.

25C to 30C these days. Since, it is naturally so warm, I am not using a heater.

You never did mention ammonia/nitrite levels. What have they been?.

Nitrites very low. Ammonia don't check.

Good luck! Let us know what happens when you make some changes.

I plan to feed lesser but more often. Also plan to have the fliter running almost all the time. I was told that a Guppy fry can be fed twice a day and that is sufficient.

Vijay

 

[rvijay07]

Correction, I have the NITRATE test kit. Readings always within limits.

Vijay

 

[Jack]

If you are turning off your biological filter daily, you are likely killing off some, if not all bacteria. Hence, your filter is useless. What do you use for biological filtration?

Feeding twice daily is really a minimum, though I am also lazy and only feed twice per day.

In the dark, plants give off CO2. That coupled with no surface agitation could definitely be causing a lack of oxygen and your fish could be suffocating.

Finally, nitrites should be undetectable. Did you mean nitrates? If you are measuring any nitrite, you definitely have a problem that could be killing your fish.

 

[rvijay07]

If you are turning off your biological filter daily, you are likely killing off some, if not all bacteria. Hence, your filter is useless. What do you use for biological filtration?

A Hagen Hang on the Back Filter. Also got gravel and soil in the plant pots.

In the dark, plants give off CO2. That coupled with no surface agitation could definitely be causing a lack of oxygen and your fish could be suffocating.

With the excess amount of plants, this can be the cause.

Finally, nitrites should be undetectable. Did you mean nitrates? If you are measuring any nitrite, you definitely have a problem that could be killing your fish.

Yes, I meant Nitrate.

 

[Jack]

I'm not really familiar with that type of filter (the bulk of my experience is in reefkeeping, where you don't use mechanized filters). Anyway, I assume it is providing mechanical and biological filtration. It doesn't hurt to turn-off a mechanical filter. You never want to shutdown a biological filter. The bacteria that "eats" ammonia and nitrite, also needs a lot of oxygen to survive. If you shut the biological filter off, you lose the oxygen and the bacteria begins to die. Many filters combine mechanical and biological filtration so you must keep running.

 

[Oscar]

I would leave the filter on at all times. The good bacteria in the filter media require oxygen to live. Without oxygen they will die and .........