Backyard Aquaponics
A place to discuss aquaponics

The thing is, a level of 1 on your nitrite, is a sheet load of nitrite

And only 50ish fish.

Vacuumed the bottom of the pool. Maybe the yabbies have been misbehaving and left some bits of themselves there.
Ph 7.4
Am .25
Ni 1
Na 40+

When I cycled my pool I ran with a Nitrite level of around 2-2.5ppm for about a month (graph here) - no noticeable effect on the fish (200 Jade Perch + 1 Silver Perch + 10 Shubunkins).

Note that this was a saltwater swimming pool - so salt levels are around 3ppt. Salt reduces the effect of Nitrite...

I'll need another 160kgs of pool salt to get to 3ppt. Might have to go that route if the nitrite does not start to lower. Will have to do a search on pool salt, something about which one is fish safe.

sorry if I'm wrong, but here goes:

the BYAP mag #1 says


So salt levels only need to be quite low to counteract the nitrite. If your fish are diseased, higher salt (3 or 5 or more?) for a period of time will help the fish to heal themselves/kill parasites. 1ppt all the time seems to be a common preventative measure, with no noticeable ill effects to plants.

wouldnt 17ppm be 17kgs to 1000 lts of water?

Nope. 17 kgs in 1000 ltrs is 17 ppt (parts per thousand).

Think of it like this 1 liter of water is 1 kg (ignoring temp and pressure).

So in your above example you have 17 kg of salt in 1000 kg of water so 17 parts of salt to 1000 parts or water = 17 ppt.

ppm - parts per million would be 17 g of salt in 1000 ltrs of water (17 g salt in 1,000,000 g water)...

Added 50kgs of pool salt. Rang the makers to find out if there are any nasties in there salt. Just sun dried sea water. $8 for 25kgs. Paid $40ish for salt for my aquarium. Sunray is the brand. Even emailed through a data sheet to the hardware shop. They sell more pool salt locally for cattle.

Thats the stuff, we get lake dried salt out here.

Dufflight

A useful link on chloride, in the prevention of nitrite toxicity, and how to calculate how much chloride you actually need to add.
http://aquanic.org/publicat/usda_rac/efs/srac/462fs.pdf

Thanks for the link. It was an interesting read.

Fish seem happy today. I have not added any more salt and will test the water tonight.

Still have 1 on the nitrite test. Added some water today. Fish still seem happy. Not giving them a lot of food. Found a small frog that still had its tail and threw it into the pool. Got about a meter before a silver got it.
http://www.youtube.com/watch?v=OIXW3ACJvEw

Readings are still the same. Fish are very active. Only giving them a little food and it does not last long. They follow you as you walk past the pool. Following the food shadow. Pushed the underwater filter lower in the water and it seems to be pushing twice the amount of water. Don't tell Frank.

Thinking of making an airlift pump after reading mylesau thread. 40mm down to the bottom then a right angle with 3mtrs of 40mm with holes drilled along both sides near the bottom. The idea being to suck in solids that build up near objects on the bottom. Have a bag over the outlet to catch any solids or have a bucket low in the water next to a Y section to catch solids. I can then have the inlet for the GB pump from there.