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Hi guys.  After cycling my system for about 6 weeks and completing start-up without fish, I added 15 tilapia fingerlings 4 days ago.  I fed them a few grams of powdered fish food and they eagerly ate it up.  I followed this with several more feedings the next day.  I think I made a mistake here.  Now 4 days in, I've lost 1 fingerling last night.  Water quality seems cloudy and there's a notable fish smell from the system (the fish food is made from fish by product).  I've tried to keep a detailed AP log and I hope someone can suggest my next steps.  My system is 50 gallons with a constant flood and drain using loop siphons and hydroton.  My growbeds are not full yet, my seedlings are still too young.

Should I do any of the following:

Add composting worms

Add a small swirl filter

Continue to not feed the fingerlings

Change water

Add (Buy immediately) more plants to the grow bed

Add more sea salt to help with the Nitrite.

 

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just to keep folks updated, I think I may have had a problem with my PH tests.  My PH is testing at 7.9.  I believe the tests showing PH at 6 may have been incorrect.  I'm now double testing with a meter as well as vials to ensure my readings are correct.  I even used my pool test kit to confirm 7.9 PH.

I did purchase a bag of builders lime to keep on hand to increase PH and I've ordered Iron chelate to support he system.  I'm continue to feed and increase feedings slowly.  So far so good.

For what it's worth Fred, I read an evaluation the other day that compared the accuracy of some of the meters to the test kits...and IF the article was right- I'd trust the test kits I think more than the meters or the strips....as a rule.

But I'm only going by the article I read...I've never owned meters (except one for the soil in my garden...and it never worked right come to think of it.)  :-)  Glad to hear fish are doing ok...

We're back up to 105 degrees today, so I'm curious to get home and see if my water stayed cool enough for my 2 koi in the tank for the test run !!!  (I trial ran the shade awning for a week in 100+ weather and the water stayed under 85 so I'm probably good.)

Go get some distilled water for your control test and to calibrate... that should be precisely 7.0

Fred said:

just to keep folks updated, I think I may have had a problem with my PH tests.  My PH is testing at 7.9.  I believe the tests showing PH at 6 may have been incorrect.  I'm now double testing with a meter as well as vials to ensure my readings are correct.  I even used my pool test kit to confirm 7.9 PH.

I did purchase a bag of builders lime to keep on hand to increase PH and I've ordered Iron chelate to support he system.  I'm continue to feed and increase feedings slowly.  So far so good.


Your local hydro store is very unlikely to have potassium bicarbonate... as the principle ingredient in their pH UP....

Their pH Up... could be anything... and they might not even know, or be able to tell you...


Jonathan Kadish said:

 

You can cheat and go to a hydroponics store to buy some PH up which is potassium bicarbonate in solution -

Your right Rupert, my PH UP from General Hydroponics list Potassium Carbonate and Potassium Silicate... not Potassium Bi-Carbonate.

RupertofOZ said:


Your local hydro store is very unlikely to have potassium bicarbonate... as the principle ingredient in their pH UP....

Their pH Up... could be anything... and they might not even know, or be able to tell you...


Jonathan Kadish said:

 

You can cheat and go to a hydroponics store to buy some PH up which is potassium bicarbonate in solution -

Johnathan, you cannot calibrate a pH meter with distilled water. And contrary to what the net or people say, distilled water does NOT have a pH of 7. This is because the pH of distilled water is not neutral, but is indeterminate. (By the very nature of what pH is and how we are able to measure it). At best, once you open the bottle of distilled and plop your meter in there, you will see an acidic reading (below 7), and it will continue to fall the longer you hold the meter in there. The distilled water (having no measurable pH) easily picks up carbon from the air, forming a weak acid. Try it.

That $0.99 cents is better spent on purchasing calibration fluid at the hydro store (and properly caring for/storing and using your particular meter, should go a long way. Just follow the manufactures instructions for maintenance and use). 

Jonathan Kadish said:

Go get some distilled water for your control test and to calibrate... that should be precisely 7.0

Fred said:

just to keep folks updated, I think I may have had a problem with my PH tests.  My PH is testing at 7.9.  I believe the tests showing PH at 6 may have been incorrect.  I'm now double testing with a meter as well as vials to ensure my readings are correct.  I even used my pool test kit to confirm 7.9 PH.

I did purchase a bag of builders lime to keep on hand to increase PH and I've ordered Iron chelate to support he system.  I'm continue to feed and increase feedings slowly.  So far so good.

Thanks Vlad... I stand corrected.

Vlad Jovanovic said:

Johnathan, you cannot calibrate a pH meter with distilled water. And contrary to what the net or people say, distilled water does NOT have a pH of 7. This is because the pH of distilled water is not neutral, but is indeterminate. (By the very nature of what pH is and how we are able to measure it). At best, once you open the bottle of distilled and plop your meter in there, you will see an acidic reading (below 7), and it will continue to fall the longer you hold the meter in there. The distilled water (having no measurable pH) easily picks up carbon from the air, forming a weak acid. Try it.

That $0.99 cents is better spent on purchasing calibration fluid at the hydro store (and properly caring for/storing and using your particular meter, should go a long way. Just follow the manufactures instructions for maintenance and use). 

Jonathan Kadish said:

Go get some distilled water for your control test and to calibrate... that should be precisely 7.0

Fred said:

just to keep folks updated, I think I may have had a problem with my PH tests.  My PH is testing at 7.9.  I believe the tests showing PH at 6 may have been incorrect.  I'm now double testing with a meter as well as vials to ensure my readings are correct.  I even used my pool test kit to confirm 7.9 PH.

I did purchase a bag of builders lime to keep on hand to increase PH and I've ordered Iron chelate to support he system.  I'm continue to feed and increase feedings slowly.  So far so good.

Fred, I hope your issue has been resolved by now, and luckily, tilapia are pretty damned tough. My advice for you, is to double-check the advice you are given on these open forums. You, my friend, have been given some questionable advice.

"Should I do any of the following:" my advice follows each of your questions

Add composting worms...yes, great source of benificials, and instrumental in mineralizing solids, IMO

Add a small swirl filter...sure, if your media bed is filling with solids and you wish to conveniently remove those solids from the system, a swirl filter will accumulate solids before they become a problem in the media. Other solutions are to add more media beds, lower fish density and feed, use composting worms, keep beds heavily planted, and/or employ the use of scuds.

Continue to not feed the fingerlings...yes, back off or quit feeding until water quality improves

Change water...yes, if you fear things may get worse before they get better, do a water change, better safe than sorry, and it will by you time to figure it out. In your case, nitrites were on the decline, so I would probably not have worried about it. Great record keeping by the way.

Add (Buy immediately) more plants to the grow bed...not necessary, but wouldn't hurt either. Plants can use some ammonia directly, which would ease the burden of nitrite, but probably not enough or not quickly enough to matter.

Add more sea salt to help with the Nitrite...yes, absolutely! I personally keep all my tanks at .5 ppt salt, just to ease stress, mitigate nitrite problems, and provide chlorides (essential for plants, and very essential for fish

Very few people need to buffer up, and those who do are likely using RO water, rainwater, or unusually soft water. Your pH chart says you hover in the high 7's. That means you will likely never need pH up. And if you ever do, seashells, wood ash (ash + water = potassium hydroxide, or lye), limestone, marble, even a chunk of concrete are readily available without mail order. If you wish to boost potassium without altering pH, use potassium chloride, sold at hardware stores for water softeners, $15 for a 50 lb bag. I've been using it in lieu of rock salt with good results.

Your cloudy water (like somebody dumped a gallon of milk in there, right?) is not a normal part of having fish, but no cause to be alarmed either. It is likely a bacterial bloom, and in itself is not harmful to fish. It is indicative of poor water quality and often accompanies or follows cycling. It will fade, usually overnight, once water chemistry resumes balance.

Standardized solutions (usually 7 and 4) must be used to calibrate a pH pen.

Lack of iron shows up as chlorosis of new growth, not overall lack of green.

Hope that helps, good luck.

Thanks Jon, appreciate the help.

I think my PH drop was a result of my PH pen reading incorrectly.  My PH does indeed seem to stick around 7.9.  I had added an air pump and perhaps in combination with composing worms has made a big difference in water quality.

I've resumed feeding and my fish are growing daily.  I'm hoping to ease up on my testing routine which has been three times a day (likely way over doing it but I really didn't want to let one of these little guys suffocate).

Thanks again for all the help everyone has offered.  

Jon

I had to buffer up and I don't use RO water, rainwater, or soft water.  My media is river rock/pebble and very stable when it comes to PH. (I tested it for 2 weeks before I even put it in my system). 

At first I had to take PH down (i used "Conc Etch" a little at a time, but then  (like so many said I would) once the system had been cycling for about 2.5 weeks...the PH started dropping and I had to buffer up.

I can't speak for others...but I have a log of everything for the last month on what I did,  and I mean everything I added including how many gallons of water on a given day,  but maybe I'm just one of the few exceptions with my system.

Good to hear, Fred. Sounds like you're out of the woods

Also good to hear of your experience, Bradly, thankyou. Water chemistry is intriguing, I should start to study it more carefully. I just finished watching a vid by Nate Storey, great info. I haven't had my well water tested, but I'm assuming I have some significant carbonates, after reading Nate's comments. Here it is:
http://community.theaquaponicsource.com/video/bringing-up-ph-levels...

My comment for Fred about not needing to add base, is because his top-up water is 8. Yes, nitrification is acidifying, but we want our water in the 6's. May I ask what your system pH was when you decided to add base? What base did you use, and what was the pH of your top-up water? Did you have to buffer only once, or is it constant maintenance for you now? I would sure like I see your data for my own education.

My local college, who shares very similar water to me, uses RO water to lower pH, and straight water to raise it. No buffer or acid required (actually not true, as their RO water is around 4-5, and tap water 8-9, but at least no bottled or bagged products).

I started fishless cycle on July 13th, after testing my gravel for 2 weeks prior to even adding to the grow beds.

My water comes out of tap at 8.2.  I did put 1 teaspoon of acid (phosphoric-Concrete Etch) in every 5 gals of water added to system.  I also would have to add acid a little everyday to get/keep PH down to high sevens.  After 2 weeks or so, PH was a little lower and I kept adding a spoon of acid or two every day or two...just to slowly bring it down to 7.2 range. 

I would add ammonia every morning and evening (clear ammonia) and some humonia (2 weeks old min.) I also added 2-5gals of my aquarium to the system as well as 2 gallons of water I had washed out my dirty aquarium filter in over a period of 2 weeks.

August 12th I noticed that the nitrites(which would be at 5) were being knocked down totally in about 12 hours to 0.  It was then that I noticed the PH start to drop slowly... (I was testing every morning and evening).

On morning of Aug 17th I noticed the PH had dropped a little more and it was down to like 6.6 , so I began putting a teaspoon or 2 of lime in the system everyday and stopped adding any acid to the water I was adding to the system to get it to 7.0 for the transfer of the fish from my aquarium in the house.

On Aug 24th I put 2-6" koi in the fish tank...and the PH climbed a little for a few days to 7.2 and 7.3 so I used a tiny bit of acid every day to slowly bring it down to 6.8-7.0 and now it's leveled off pretty much at these numbers.

I do emphasize one thing... I carefully tested and added the acid and the lime & potassium bicarb a little at a time and then test 12 hours later again and make small adjustments.

So there you have it...  at first I needed acid to bing PH down, then small amounts of lime and potass bicarb (alternated) to ease it back up in small steps.  I'm interested to see what this week will bring and whether or not the bacteria growing will eventually counter act the naturally high ph out of my tap.  Maybe once it all settles in the high water PH will counter act the nitrification process...

I think everyone needs to have a little acid on hand as well as a little base product of some kind at first anyway...just to slowly add to keep things as close to desired PH as possible.  This "start up" is just a test run for me for next spring's real "start up"...so I'm monitoring everything and moving slowly and cautiously.

The only variable for me that will change next spring is the number of fish will greatly increase, but since I intend to grow them in the aquarium in the house for the first 4 months... I will be able to slowly add them to the system outside without overloading the outside system.... while carefully watching everything and what effect the addition of "x" number of added fish have on it.

 

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