Need Help! 3 Plecos Died In My Tank And I Don't Know Why

[irishamy20]

Hi I am new to the forum.  
I have a 10 gallon tank with 3 platys, 3 cory catfish and 2 African dwarf frogs (and 5 baby guppies in a mesh box that will be moved to the other tank we have set up in another week or two).  I decided to get a pleco because while my catfish do an incredible job cleaning up leftover food I noticed I had some algae growing along the backside of my tank.  Because I don't have a large tank I was instructed to get a rubber lipped plecostomus because they don't grow as large as other plecos.  He died after the first day of being in the tank.  We took him to the store along with a water sample and they exchanged him for me and told me my water levels were great.  So number 2 I brought home was a clown pleco (which I found out doesn't eat as much algae and purchased him some driftwood) , he died after 2 days.... by now I was thinking that it was something wrong with the pet store (Petsmart)  so I went to a privately owned little fish store in town who I also gave a water sample to and he was impressed with my levels and said there shouldn't be any issues like I am having so I came home with number 3 a speckled pleco who died after 4 days.  Why is this happening  I have had 3 different types of plecos pass away and my water levels are fine, my other fish are healthy, my frogs are plump, the catfish are extremely playful and the baby guppies are thriving and growing rapidly.  Any help/insight/advice is welcome.  I refuse to put another poor pleco in this death trap until I figure out what I am doing wrong.  

 

[LunaBug]

Is there a possibility that the catfish are bullying the pleco somehow?
I know this may sound like another silly question but are you floating the bag before adding them in?
After the two from petsmart did the same thing I would tend to blame it on the store but by that third one from the LFS dying as well it makes me question the tank itself. You said that all the water parameters were good so that just leave temperature and tank-mates to question.

 

[Maehlice]

Hello and welcome to the forums.  

 I'm sorry to read an event like this is what brought you here.
 
To give us a better idea of what may be going on, a full list of parameters you've tested and any more details about your tank would be helpful:
 
What were the Ammonia-Nitrite-Nitrate levels?
 
How frequently and at what quantity do you change the water, and did you do any water changes during those 3 time periods?
 
What type of water do you use (tap, RO, etc)?
 
What is the temperature, pH and GH of your water?
 
Did the casualties show any sign of physical trauma or strange behaviour before dying?
 
Is your tank planted?
 
What do you feed your fish, and did the new additions appear to be eating?
 
How did you condition the fish when introducing them to your aquarium?
 
(I'm hoping I didn't miss anything.)
 
 
Plecos are typically quite hardy, so I definitely find it odd.  My only guess is that with all the bottom feeders in a small tank like that, your cats might be the culprit defending their turf.
 
EDIT:  Looks like LunaBug and I were thinking the same thing about the cats.

 

[frapadoodle]

Tank woefully overstocked.
How long has it been running?
Corys are passive and do not 'defend thier turf'.
The best way to combat algae is to determine the cause and correct that.
If you feel you need algae control go with nerite snails in a tank that small.

 

[SarahR]

You didn't say the size of the Plecos.  Small and baby plecos can be delicate in my experience, and pet shops frequently overstock and underfeed them.  Because of their nature they can take a while to settle and eat in a new tank so many are thin and undernourished .  They are also difficult fish to net safely, many times in shops they can be unknowingly injured from rough handling. Don't be mislead by a pet shop water test, it is too basic.  Something is probably out of balance if algae has suddenly appeared.  
 I wouldn't blame Cory cats, they aren't aggressive and plecos are well armored.  A ten gallon is really too small in any case, and it's already heavily stocked.  Adding yet more fish isn't likely to solve an algae problem under those conditions.  Large water changes, perhaps removing a few fish if possible, and carefully avoiding overfeeding are better options.  You should specifically feed cory cats a sinking food, rather than deliberately overfeed the other fish so some makes it to the bottom.  They will still hunt for and clean up any leftovers, but ideally there shouldn't be any.

 

[ech0o]

I am betting this happened from acclimation.  Pleco need to be drip acclimated for some time before introduction as they can be sensitive to changing water conditions.

 

[irishamy20]

I hate to sound silly but what is drip acclimated?

 

[fluttermoth]

You stand the open fish bag in a large jug or bucket (make sure it can't fall over!) and use some airline, with a knot in it to slow the flow, to drip tank water into the fish bag.
 
Once the fish bag is full, you can either sink the bag in the tank and let the fish swim out, or net the fish and add it to the tank.
 
It should take a couple of hours to do and gives the fish more time to adjust to your water.
 
I would agree with the other posters that your tank is too small for any kind of plec really though.

 

[SarahR]

It's a far better way to add almost any new fish to a tank.  
Rather than floating the bag (which isn't really a good idea) you pour the fish and bag water into a container and hook up an airline with either a control lever valve or simply knotted.  Using the airline, you start a siphon from the main tank and adjust it to drip very, very slowly into the container, a drop every second or two. It should generally take an hour or more for the water volume in the container to even double.  That way the new fish is slowly introduced to all the tank water parameters, not just temperature.  For most fish, sudden PH changes are far more dangerous than a slight temperature difference.  

 

[irishamy20]

I just want to thank everyone for taking the time to respond.  
I have a few questions but I'll answer some of the questions that I was asked first.
 
-The tank has been running for 6 months and has never had a death until the plecos (with exception of mommy guppy who sadly passed away during birthing)
-it is not currently planted but I would like to in the future once I know more about it
-the fish/frogs eat a variety of flakes/brine shrimp/blood worms
-temperature is at 78
-water is clear and 25% changes once a week. Filter replaced as needed (usually every 3 weeks)
-I do not believe the Cory's are the culprit,  they are friendly and playful
-The tank originally had some nippy guppies so they were moved into a separate tank and we decided to get 3 platys which have been friendly as well
-the baby guppies are only there until their awaiting tank is cycled (in the process)
-I will provide the parameters tonight
-the algae started when the tank had to be moved and it is currently situated near a window.
-The tank is aerated
-we use regular tap water
-the plecos didn't show any signs of distress/trauma and seemed to be healthy  
 
Ok few questions
-I do not want an overstocked tank so what would be appropriate for the 10 gallon?
-should I try a snail instead of pleco?
-if all of the other fish are healthy and happy but my pleco keeps dying how likely is it caused by the fact that I haven't been drip acclimating them ( if thats the issue then I would be relieved, I don't want to lose anyone else) 
 
Thanks again everyone

 

[Maehlice]

Ok few questions
-I do not want an overstocked tank so what would be appropriate for the 10 gallon?
-should I try a snail instead of pleco?
-if all of the other fish are healthy and happy but my pleco keeps dying how likely is it caused by the fact that I haven't been drip acclimating them ( if thats the issue then I would be relieved, I don't want to lose anyone else) 
 
Thanks again everyone

• The definition of "overstocked" is largely a subjective question, because there is not [that I know of] a universally-accepted rule or calculator for stocking.  There are a wide range of conditions which lead to different conclusions.  My definition of overstocked is factored on 3 things:  size of tank, number of "homes" and bioload.   Here's my 2 cents:
  Size.  Your tank isn't overstocked.  I believe it certainly would be with a pleco.  Because your fish are relatively small and each dwell in their own zones (cories and frogs on bottom, platies on top/middle), the tank isn't overstocked from a space standpoint.  Having 5 bottom-dwellers lends more to the idea of overstocked, but since frogs sleep most of the time and dwell mostly near the top (all over, really) when awake, I think it's okay.
  
  EDIT:  In the wild, each fish has hundreds -- even thousands or millions -- of gallons to call home, so even a single fish in an aquarium can be thought of as "overstocked" by comparison to nature.  Just food for thought.
   
• Territories.  I have no idea what your tank looks like.  I'll assume it has rocks and plastic/silk plants and all the decor necessary to give each fish a feeling of "this here rock/tree/plant/cave/corner/shadow is my home".
   
• Bioload.  Possibly overstocked, but I don't know enough about your weekly measurements to say either way.  "Overstocking" from a bioload standpoint depends heavily upon how frequently you maintain water changes and if the Nitrate level ever reaches 40+ ppm.  Ultimately, as long as the nitrates never reach 40 ppm and preferably stay <10 ppm, who's to say you're overstocked?
  
  This is my practice when considering whether bioload is too great ... measure the tank's ppm right after a water change, then measure it again in exactly one week.  If during that week's time your tank increased its nitrate level by +10 ppm, you're fully stocked.  The reason I say this is because to maintain <40 ppm at that rate of increase, you must perform at least a 25% water change each week (50% weekly to maintain <20 ppm, 50% bi-weekly to maintain <10 ppm).
   

[*]A snail would definitely be a better addition than another fish.  They do increase bioload but won't really offend anybody since they seldom leave the glass.  Nerites lay eggs on the glass like there's no tomorrow, so you will still need to clean the glass of them if you want it spotless.
 
[*]Given everything you've said and the hindsight reconsideration that cory cats are peaceful, poor acclimation is the only thing that makes sense.  I've found pH shock is the greatest killer.  If you introduce new fish in the future, doublecheck your pH versus the LFS's pH.  If it's a huge difference try to acclimate the new fish as slowly as possible -- potentially even setting up a QT (which could be as simple as a 5 gallon bucket with an airstone and heater).

To a lesser extent, consider also KH and GH.  I have no articles or research to back up this statement, but I was told it and abide by it simply because it makes sense to me and is not difficult to follow:  A drastic and sudden change in hardness can shock a fish's nervous system due to the change in the water's conductivity.  Conductivity can only be measured by electronic devices, but a lay-person can add KH and GH ppm to guesstimate TDS (which is the major contributor to conductivity).
 
That's all I got (which appears to be a frickin lot now that I look back at it 

).  I hope it helps.