Backyard Aquaponics
A place to discuss aquaponics

Please check out these close up pictures of my Tilapia from today:
https://imgur.com/a/KHlhC

New fish to a new tank 2 - 3 weeks old in cycle. It is in an inner city elementary school; and school recently started. Fish came pale white now most are darkening. Eye color is changing I just noticed. They are eating and fairly actively swimming around, more than when we first got them.

Plants are growing, I can assume nitrates are being created, however API 5 in 1 Aquarium Test Strips are reading Am. around 0.75 ppm and Nitrites are going up to 3.0 ppm as well.

I salted the tank 5 TBSP for a 250 gallon tank 5 days ago in preparation for the Nitrite spike and have been buffering with Seachem Netural regulator, a Phosphorous based buffer that is supposed to help with Amm. and nitrite toxicity. Today I put in 2 teaspoons along with a 5 gallon top off.

Should I start doing some 25% water changes - that would be over 50 gallons! (I think I overfed the past 3 days, really not much food at all considering their size, but still feel like it was too much)

What are your recommendations? More salt, PWC? I know I need to reduce reduce feeding, like to ever 2nd day or 3rd day. The dark color ones seem more aggressive and nip/ suck at the white ones. Is the color relating to stress, mating, or maybe they are trying to coat their gills by stealing slime coat from the white ones? I don't know. Any shared experience or knowledge would be much appreciated. Thank you!

Your a brave man cycling with fish. In front of a room full of young kids. Is there a way to remove the fish so you can fishless cycle. So you don't have to worry about killing all the fish? Have you sexed your fish to see exactly what you have in the tank? Although Tilapia do change coloration as part of their mating cycle. I do not know enough to diagnose their present condition. Try to send Chappo a PM

Your water conditions are near enough toxic for your Tilapia,at .75/.8ppm Tilapia start dieing,close to 5ppm nitrite same thing.
Stop feeding,
Water changes to reduce Ammonia and nitrite,
If possible take a couple of fish out,theres nothing wrong with cycling with fish providing your patient and don’t over stock to quickly.
Salt the tank,1 kilo to 1000 litres gives you 1ppm,you want 3ppm to help with nitrite poisoning or brown blood disease as its called,Tilapia are fine at 5ppm.
Colour will be stress related.
Tilapia chase and nip each other constantly,its all to do with territory and females.

Umm.. I had talapia survived higher nitrite ppm than 5.. but you got to stop feeding IMMEDIATELY... test ammonia as well.. once ammonia starts to drop.. nitrite will follow as well.. gluch and keep us informed.

1) There's nothing wrong with cycling with fish, just do it it with a very light fish load. It sounds like you are doing everything right with salting.

2) Worry less.

Tilapia colors is like weather here in texas.. if you dont like it right now just wait a few hours.. They change constantly. I doubt the colors have anything to do with your water quality.

The toxicity of nitrite comes from inhibiting the fish's ability to get oxygen from the water. If this is happening to your tilapia you may see them trying to suck air at the surface and their gills will be more brownish in color than red. Salting helps as does good aeration.


I have fish cycled dozens of systems in the last 5 or 6 years and not lost a fish to toxicity yet. I dont really understand the fascination with fishless cycling for people who understand the process. Just start small and be patient.

The toxicity of nitrite comes from inhibiting the fish's ability to get oxygen from the water. If this is happening to your tilapia you may see them trying to suck air at the surface and their gills will be more brownish in color than red. Salting helps as does good aeration.

No Nitrite poisoning or correct name Brown Blood Disease is the bloods inability to transport oxygen due to the production of Methemoglobinemia,this is formed from Hemagoblin by high Nitrite levels,the chloride in salt competes with nitrite at the gills,the fish taking on more chloride than nitrite so holding off brown blood disease.

Tilapia colors is like weather here in texas.. if you dont like it right now just wait a few hours.. They change constantly. I doubt the colors have anything to do with your water quality.

It could be the poor water conditions that are stressing the fish hence the colour change,in fighting mode they will darken,in poor conditions they will start going pale.One way to see after you do a water change just monitor the fish colour.

cookie,ok so you didn’t have any die but what harm or stress that you couldn’t see were you doing to the fish,5ppm is Aquaculture figures for deaths in Tilapia.

You are completely correct but i dont know how that is any different from what i just said, just the difference between low level explanation and high level.





that's funny because my males get lighter (white with red heads) when they are getting territorial and ready to mate. The females get darker the longer they brood/are stressed... And of course they change colors when it gets cold and when it gets hot and every time in between. Stress can cause color change but it's not the only reason colors change and in the context of this poster's water quality my opinion is it's probably not related, and if it is i wouldnt be super worried about it.

I think many people tinker too much and just cause more stress, when the present problem is sufferable.


brian

Sorry bcotton just nit picking,

I think many people tinker too much and just cause more stress, when the present problem is sufferable.

i totally agree.

Stress can cause color change but it's not the only reason colors change and in the context of this poster's water quality my opinion is it's probably not related, and if it is i wouldnt be super worried about it.

Again i agree with you but in some instances in it is an early indication that something might not be quite right and i feel in this instance it could very well be the water conditions causing the colour change, at the end of the day from what we have posted here we have given the poster positive advice and maybe the first steps for him to address the problem.
I have Niles and they go very dark when they are pushing each other around and if i get a fish that succumbs to the bullying and tries to hide they will go pale....

@bcotton I completely agree with everything you said. no point repeating because you were very complete in all information.