Update: Values 0 For 3 Days!

[iluvguppies]

One of the ways that people can do a fishless cycle is to just let some fish food rot in their tank. The first day or two they don't get much ammonia but after that it can be quite dramatic how well it works. By dumping way too much fish food into a tank, you are temporarily going to see a huge increase in the bioload. Once the rotting food is effectively cleaned out, that spike should stop and the water should improve. I see you are adding salt to start moving towards a brackish tank. Make sure that you use sea salt, not typical aquarium salt. Brackish water, in nature, is a mix of ocean water and river water so you want to use the same salt that is used to make ocean type water for a reef tank to mix up your brackish conditions. By the time you get significantly brackish conditions, the guppy will be very uncomfortable in that tank. If you want a traditional freshwater fish in there, try a pet shop molly. They can tolerate salt all the way up to pure saltwater.

Thnx for the reply.....it must've been the food as the levels have now dropped back down to 0 without further w/c.
Yes I'm gradually moving to slightly brackish tank set up (1.005 SG) as we rescued a emaciated Dragon (violet) Goby and he was kept in FW but we know that it's optimal forhis health to be in brackish water. We also found out that guppies do well in slightly brackish water and we are acclimatising them very slowly over the course of a few months, so that the filter bacteria as well as the fish aren't stressed too much. I'm using marine sea salt on recommendation from nmonks (who has been very helpful). Let's hope that things go well and we have no more set backs

Nikki