Stunted Fish Growth

[merlinblack]

Hi folks,

I have a silver shark thats abput 3 inch (should grow to 12-15") at the most and hasnt grown at all in the year or so that I've had it, its in a 5'x 2'x 2', previously I had it in a 5'x12"x15"
Also I have 2 synodontis flavitaeniatus stunted at a similar size, red tailed chalceus stunted at about 5" and signal sharks at about 4" (not sure how big signal sharks get).

Any ideas on what could have caused it?
I have a few ideas myself but see what everyone else thinks

Thanks

 

[meguro]

Not frequent and/or large enough water changes. Lack of proper diet.

 

[merlinblack]

Not frequent and/or large enough water changes. Lack of proper diet.

I do a fair amount of water changes and amkeeping nitrate rock bottom with plants etc. maybe I need to feed them more but they're not thin or anything. I susspect some of them could have been stunted when I bought them as they havent grown at all in the time ive had them, the red tailed chalceus ive had since they were small so have grown a bit so might have had poor water quality at sopme point during the time ive had them

 

[drobbyb]

May I ask your waterchange frequency and percentage? Also, what are you feeding?

 

[snowflake311]

Some fish slow down growth. Some are just smaller like some people. But good diet and clean water helps. My cichlids grew like a weed for the first few months once they are half the size they should be they slowed down. I feed the same stuff do the same wc. They just slow down. Domestic fish don't get as large as the wild ones most of the time.

 

[merlinblack]

May I ask your waterchange frequency and percentage? Also, what are you feeding?

Frozen bloodworm & hikari lionhead pellets mainly, sometimes a bit of lance fish but thats for the frog mainly

 

[merlinblack]

Some fish slow down growth. Some are just smaller like some people. But good diet and clean water helps. My cichlids grew like a weed for the first few months once they are half the size they should be they slowed down. I feed the same stuff do the same wc. They just slow down. Domestic fish don't get as large as the wild ones most of the time.

I dont have a set time period for changing the water, I used to just do a big water change when it got to 50ppm nitrate or so. This year I bought an RO unit because the water is really hard round here and I couldnt grow any plants other than vallis. Since using RO I've been growing mainly floating plants but they grow like mental and i have to take them out, also I set up a box filter with denitrate in it and I tested the water last week and the nitrate was pretty much undetectable (test goes down to 5 ppm and Im guessing it was about 1 ppm).

I've had silver sharks before going back 15 - 20 years when I lived with my mum in a soft water area. I got them as 2" tiddlers and I got rid of them when they got to 10" which I dont think took overly long to get to. I think that hard water stunts fish as I've bought fish locally and they stay stunted but if i get them from further away they do a lot better.


In my 5'x2'x2' I had mature fully grown fish that i used to just feed once or twice a week but they got wiped out with whitespot early this year, some of those fish were well into their 20's.
I had a 5'x12"x15" that i used to put the young fish in to grow on which are now in the big tank but all seem to be stunted for some reason. They could have become stunted while they were in the smaller tank, I just have 3 reedfish and 1 syno that ive added while they've been in the big tank.

 

[OldMan47]

No water changes because the denitrator is working is wrong. We use the nitrate build to tell us when the impurities are starting to build up in the tank. The nitrate itself is just an indicator. Nitrates are harmless to most fish at well over 100 ppm but we recommend a build of 20 ppm because that keeps the overall water quality good. By using a denitrator you are hiding that clue to when a water change may be needed, you are not removing the need for a water change. By removing plant matter, you are indeed removing some of the impurities as plant matter. What none of us know, because we are not set up to test it, is what else is being left behind.

 

[bitteraspects]

the problem is likely the water change schedule (or lack there of).
its not the nitrates that cause fish stunting. nor is it tank sizer (contrary to popular belief). fish release a hormone (GH hormone) into the water which in high quantities cause stunting. smaller tanks create a bigger problem because of the smaller water column. less water means the intensity of the GH hormone present in the water is even greater, and thus requires even more water changes.
this is one of the main reasons for daily PWC in "grow out" tanks and frequent WC for breeding set-ups.

weekly 25% WC is pretty standard practice, and really isnt asking much of any fishkeeper. but if you have fish that you know will get big or have an overstocked tank, you should consider doing more than the standard 25%/weekly.

 

[merlinblack]

the problem is likely the water change schedule (or lack there of).
its not the nitrates that cause fish stunting. nor is it tank sizer (contrary to popular belief). fish release a hormone (GH hormone) into the water which in high quantities cause stunting. smaller tanks create a bigger problem because of the smaller water column. less water means the intensity of the GH hormone present in the water is even greater, and thus requires even more water changes.
this is one of the main reasons for daily PWC in "grow out" tanks and frequent WC for breeding set-ups.

weekly 25% WC is pretty standard practice, and really isnt asking much of any fishkeeper. but if you have fish that you know will get big or have an overstocked tank, you should consider doing more than the standard 25%/weekly.

25% a week for all my tanks is about 50 gallons and I need to use RO water as the water round here is too hard so is a big deal for me.
I doubt the fish shops do 25% water change per week and they tend to overstock the tanks so could be that they became stunted before I bought them?

 

[Truck]

there lies your problem, RO water contains no nutrients for your fish, so they will be stunted, there are minerals in tap water which fish need in order to stay healthy and grow. That is presuming your not re-mineralizing it?

 

[drobbyb]

It could be a combination of many things here. If you want fish to grow, 50% weekly waterchange and a good varied diet will do it. This eliminates the hormone problem and provides the fish with the needed minerals and nutrition.

Stunting is a cumulative problem. It isn't like a disease and there is no cure. A fish that has been stunted a little will resume normal growth when it is placed in the proper conditions, but the original organ damage won't go away.

 

[bitteraspects]

25% a week for all my tanks is about 50 gallons and I need to use RO water as the water round here is too hard so is a big deal for me.
I doubt the fish shops do 25% water change per week and they tend to overstock the tanks so could be that they became stunted before I bought them?

actually, LFS likely do 25% weekly, maybe more. they have a schedule and payed employees who handle those things. one of the perks of having payed employees. i wouldn't be so quick to blame the LFS ah you obviously aren't doing enough WC yourself. also, 50g is cake compared to a lot of peoples WC schedule. (i do 3-400g/week)

 

[snowflake311]

You have only had these fish for a year? How big were they when you got them?

Longer lived fish take years to fully grow. It can take 2-5+ yr for a large fish to get to be full sized. Honestly I would not worry about it. IMO it seems like if they are about a year old and half the size they should be it's fine. red tailed chalceus get to be around 10" your is 1 yr and 5" that's fine I'm sure he is still growing he just slowed down. Females tend to be smaller 8". These fish can live to be 20 yr.

synodontis flavitaeniatus gets 6"

signal shark ?? Do you mean Labiobarbus festivus aka signal barb? They get 9".

Now in 2 yr from now they are still small then you can freak out.

 

[merlinblack]

there lies your problem, RO water contains no nutrients for your fish, so they will be stunted, there are minerals in tap water which fish need in order to stay healthy and grow. That is presuming your not re-mineralizing it?

I normally mix with about 20% of my tap water about, last time i used RO right but made used the dosage for very soft and found it to be pH 5.8 so I then added a small amount of tap water and some potassium carbonate to adjust the pH, I also added some trace elements for the plants.

No water changes because the denitrator is working is wrong. We use the nitrate build to tell us when the impurities are starting to build up in the tank. The nitrate itself is just an indicator. Nitrates are harmless to most fish at well over 100 ppm but we recommend a build of 20 ppm because that keeps the overall water quality good. By using a denitrator you are hiding that clue to when a water change may be needed, you are not removing the need for a water change. By removing plant matter, you are indeed removing some of the impurities as plant matter. What none of us know, because we are not set up to test it, is what else is being left behind.

I did a 90% water change a couple of months back and its a 5x2x2 with only 15 - 20 small to medium sized fish. I've had much more crowded tanks and done much less water changes and had fish grow well in the past back when i lived in a soft water area.