Foubd 10 dead 1 week old fry today

I know this is a common issue with breeding bristlenose for a first time (thats why i read so much and joined this forum before begginning) but today i woke up to my first fry dead..
I specifically tried to choose parents from different bloodlines (maybe ive been told fibs)
Water parameters were ph:7.4, amm: .25 (so put some stability in to build up bacteria), nitrate and nitrite:0
Water temp: 26
144L in the tank, only bristles, 500L filtertration per hour
Feed veggies everyday, driftwood and caves in tank
10% water changes everyday since fry hatched
Im puzzled.

And in the past day the adults are keeping near the top of tank with there noses almost out of the water...

Couple other factors:
-Was water used for changes aged?
-Air stone?/Light&plants?
-Is the temperature stable?
-CO2?
-GH, KH?
Behaviour indicates lack of oxygen. Some plecs (bns too) are able to breath atmospheric air.

Used tap water, which has a ph of 7.5 usually,
Did have plants but they destroyed them, have new ones to put in though,
Yes light, no air stone
Temp never dropped below 25 but was a really cold night last night
Dont have tests for those at the moment

Yea lack of oxygen is what i was thinking
Ill put my new plants in now and see how they are by tonight and ill re test the water now since i gave it a good clean and 25% water change this morning

Other thing i was thinking that, that little spike in ammonia from 0 to .25 was due to me taking the plants out ( to replace) and the added overload of fry, there fore filter cant break down excrete?

Plants are back in.
Gunna get an air stone today.
You reckon i should be using ore boiled water in the tanks instead?

I'm assuming that your tank has cycled already?
Stock?
Tank size? If >125l, your filter is on a bit smaller side. Bacteria settle on gravel too, more porous the better. But you might be killing them off with chlorine, if you're using the water straight from the tap (we have it here, don't know about Melbourne). Let it sit in open container for at least 24h. There's something sold as "tap water conditioner", but I don't ever use it. More on that:
http://www.bristlenoseworld.com/t4727p15-emergency-need-help#33777
Ammonia level shouldn't be affected by removing the plants. Did it rise after you started changing the water so frequently?
I prefer to have over filtration, all species I have like strong current.
If you meant RO water-I don't recommend it, there was topic about it somewhere.

Yes tank has been fully cycled for 2 months, bristles have been in for 1 month, 2 fully grown, 2 7cm and 4 small bristles plus the fry that came. Was only ment to be my breeders in there but im about to sell the others.
Tank is 4 ft, holds like 160L comfortably after gravel.
I usually had 144L in there but now i keep it around 100 as i know filter isnt the greatest

Pre sure it started to rise when water changes were more frequent

Ment pre boiled water sorry*

Ive put 5 plants back in there, and am gunna empty out the fish except for the three i want to keep.

You reckon i should add some water thats sat for a day aswell to the tank? And always from now on?

for my fry tanks i only use aged water and change 25% every 3 days

Aged water as in, tap water thats sat for 24hrs or so?

Correct. 48h even better.
BTW:
Too small filter cannot circulate the water=> O2 cannot be delivered to every part of the tank. Nitrification requires oxygen.
I don't know the levels of chlorine and chloramine in Australia, but in general:
chlorine kills bacteria=>kills your nitrifying b. too=>nothing to consume ammonia.
http://www.bristlenoseworld.com/t1923-thanks-button-thankyou-all

Too small even if theres only 100L?
Shows how well fish shops know there products lol.

So bristles are still hanging near the top, theres three plants in there and about to pick up another 2
Would my fish be safer in my new tank for a day or so (its done a seven day cycle with stability) and has been cycling for about 1.5weeks, i know not ideal, but id never lost a fish since today and dont plan to loose another

How ling will it take plants to oxygenate water again? There about 20cm high each and pre bushy
Dont remember what theyre called

Flow rate = volume of the tank x >4. It's long tank, so I'd use 2 HOB filters on each side, or canister f. with inlet on one side and outlet on another.
More water, the better, by adding more water you'll dilute ammonia concentration. Keep on with stability, stop with chlorine and you should be fine. If you move all your fish into new tank at once, you'll get ammonia spike no matter if it was 1,5wk or 6 months.
As the water moves on the surface, oxygen dilutes in it.
Plants need CO2 for photosynthesis, easy way: Seachem Excel.
I use air stone only at "night" - everything's is on timer.

One'd say I'm nuts about filtration (7-8 times tank vol.) and I admit it might be overkill, but having whirlpools it the tanks I only do 15-20% water ch. weekly and it works.

Please explain inlet and outlet?
As you can see im still very new to the whole thing but oretty sure ive figured out what i want to study at uni next year!
Im gunna go buy anither 500Lph filter tomorrow for both 4ft tanks, so itd be 1000Lph filtration for 160ish litres of water each tank, enough?
Ill buy sechem excel for the Co2 aswell, plus more plants.
Hopefully fish will be happier.

Ammonia, nitrite, nitrate, and Ph all constant when i checked again so ive ruled that out
But, one of my adults is dead now,
Should i move them out?

Inlet= intake, pipe and hose taking the water from the tank to the canister filter. And outlet - from filter to the tank.
Hell knows what's going on now. Chlorine might affect the fish too. Might be something else. Did you use any other chemicals? Salt, copper?
Were the dead bloated?
I'd move one or two today and keep testing the water in new tank. If nothing happens, another in 2-3 days. Theoretically you introduced n. bacteria into the new tank with Stability. Pour some more, if instruction allows it. To the old one as well.

Yes she was bloated
No other chemicals
Okay. Thanks mate

Kh was a little low, and ph a little high when i talked to my friend at fish shop, added some kh powder to the tank to lower ph and bump up kh, also increased filtration in both tanks from 500 to 1500 (but will run them at 800-1000 at night otherwise i wont be able to sleep lol) air pumps with bug ass air stones are in both tanks now aswell
Only 1 of my two males is still cruising around the top but its only been about 20min
Others are starting to swim around again
Thank you heaps for your help K, really appreciate it.

One last question kaban,
How long do you add flourish excel to the tank after initial use, it actually doesnt say on the bottle
Just says 5ml for every 200L every day or other day?

Yes, it does. => directions.
http://www.seachem.com/Products/product_pages/FlourishExcel.html
I do every day, unless I forget,
Oh, how long? As long as you wanna feed the plants.

So try work this out, after i moved out all my bristles, all the girls died but my 2 males are alive
Only the girls died...

 
If:
-there was no new decorations, caves in the tank that might release any poison,
-water was fine ammonia, n&n-wise,
-no food was fermenting,
-no chemicals except you mentioned,
the only thing I can think of is chlorine and chloramine. More frequent water changes was the only new factor, right?
I suspect it worked just like salt or copper - killed the gut bacteria. Were they all bloated?
I'm sorry I didn't help.

Since you evacuated survivors and we cannot tell for sure what caused the problem, I'd consider restart of that tank.

Yea the symptoms matched poisoning thats the only thing i can think of.
Doubt it was the paint on the deco cause theyve had them for month, did buy a couple of new ones but the first died before i even put them in,
Ill go the fish shop tomorow and see what i can get for poisoning, hopefully i can atleast save my males, ive got filters running at 1500L per hour, and air pump slamming the water trying to bubble it out in the new tank theyre in.
Guess ill learn from my mistakes but its really heart breaking to loose my little buddies.
Really appreciate the help though.

Double dosage of prime added, all four air stone outlets pumping in the survivor tank, filtration 1500L per hour, with large gaps between outlet and surface of water to create bigger splash for oxygen dilution, water temp down from 25 to 22-23 to try and improve dissolved oxygen levels
Hope my little men get through the night.