Fishless Cycling Problem

How close should i get to my gh? Got water down to 12 and tank is 7

Got GH down to under 10 so have out fish in tank. So fingers crossed everyone gets on ok. Have kept light off tonight, will put on tomorrow morning for an hour to see what's going on.

Fingers/everything very tightly crossed for you and all the fish.
 

Ok baby steps but everyone survived the night. 😀

Hi Guys

What is a safe nitrie level?

nitrite is 1ppm, will do  a water change, 50% ok?
just checking nitrates

With a nitrite of 1 you need to change as much water as you can. There is no safe level of nitrite and it must be kept below 0.25. Even a 50% water change will only get it down to 0.5.

Nitrite gets into the blood and binds to the haemoglobin preventing it from taking up oxygen, in the same way that carbon monoxide does to us.



However, instead of a water change it is possible to mitigate the effects by adding salt to the tank. There is a calculation to work out how much. I've put your numbers in brackets

1. Multiply the test reading by 10 - (1.0 x 10 = 10.0)
2. Calculate the actual volume of water in litres - (with a 125 litre tank this is probably 100 litres)
3. Multiply the numbers from #1 and #2 - (10 x 100 = 1000)
4. Mulitiply the number from #3 by 1.5 - (1000 x1.5 = 1500)

You need to add 1500 mg salt, which is 1.5g salt by dissolving it in some tank water then adding that to the tank.
The tester will still show nitrite.

If the level of nitrite goes up you need to add more salt. But only enough to counteract the extra nitrite not the whole new amount.




How many new fish did you get, and how many were in the tank before you got the new fish?

Actually, any form of sodium chloride is fine including table salt or cooking salt. The amount of 'added ingredients' (eg anti caking agents, iodide) is so small as to be negligible. To quote one source, for the added ingredients to cause harm the amount of salt would have to be so high it would pickle the fish first.

That explains the nitrite - you added twice as many fish as were already in the tank. You had enough ammonia eaters for that number but not enough nitrite eaters

If the nitrite is zero, you don't need to add any salt. But if it creeps up again you can add some. Just put the new nitrite reading into that calculation instead of 1.0.


Salt is not a good thing to use routinely. It harms fish that originate in water that doesn't have it - in other words it is not good for any fresh water fish. It's just that it is less harmful than nitrite, and it is only used until nitrite is gone.
No form of salt should ever be added to a fresh water aquarium except when there is nitrite in the water or the fish have whitespot (it can be used as a cure for that).
Once the need for salt is gone (zero nitrite or the whitespot is cured) the salt is removed from the water gradually by doing water changes and not adding any more salt.

Aquarium salt is just plain sodium chloride, the same stuff as table salt but without any iodide or anti caking agents.
At 1 tablespoon (15ml sponful) per 20 litres, that is a huge amount of salt. A level teaspoon (5ml spoon) of salt contains something like 6g, and the calculation requires a quarter of that in 100 litres!!!

If I remember correctly, API aquarium salt is crystals rather than a powder which does make it difficult to compare a spoonful of that to a spoonful of table salt. I would still weigh it rather than measure it with a spoon. I have kitchen scales which weigh to a gramme. For a half g I would weigh double what I need then divide that amount into two halves.




A lot of companies that make aquarium salt, and a number of old time fishkeepers do recommend adding salt to a tank on a routine basis. This is because decades ago no-one knew about the nitrogen cycle. They did not know about ammonia and nitrite, and there were no testers for them anyway. But it was discovered that adding salt to the tank stopped their fish dying - and we now know that is because it blocked nitrite from binding to the fish's blood.
We now know about nitrite and what to do if we find any in the water. But that doesn't stop old time fish keepers telling everyone they should still add salt, and it doesn't stop companies selling aquairium salt as it costs next to nothing to make and earns them money.

It seems my Nitrite spike has gone, just checked and it was 0.03ppm. Do you think I am safe not checking again until the morning?

Fish seem ok, although one of the Rasboras is a little quiet. Rest and the Phantoms seem quite active.

Did check just now, 9pm. Ammonia 0.05, Nitrite 0.08 and Nitrate 2.53. So things seem to have settled down back to normal.