Backyard Aquaponics
A place to discuss aquaponics

I would not add any fish until your ammonia had settled down properly.

Same system though right? You're just moving them from the sump to the tank.

At that pH and temp, the chart says ammonia of 3 is not poisonous. This is a good thing. However I bet it isn't real nice for them. Just keep an eye on them, I'd still try to get it and/or the pH down (at some point people used coir peat?!)

+1 don't feed - keep a close eye on it. Fish also get stressed by sudden changes in light (e.g. flashlights), temperature changes, pH changes, water clarity changes.... i.e. pretty much anything.

Have taken half water out and replaced with fresh tank water to try and bring ammonia level down and moved silvers into main FT and left goldies in sump. Also turned heater off to keep temps down until ammonia drops does that sound like i am doing the right thing?

I think I read somewhere that your growbeds are 1250L total and 1000L FT.

Not sure if it works the same for SP but I think the stocking levels of 70SP could slightly on the high side for your system. Especially for a cycling system. But I could be wrong.

Not sure if you have algae problem yet. If not, make sure you cover all your tanks from sunlight. An algae bloom would cause fluctuation in your pH over the day. From memory, pH goes up during the daylight and so does temperature... Hence if you look at the chart, especially if you only test your water in the evening, you might think ammonia of 3 is fine, but due to the pH and temperature fluctuation on a hot day, the ammonia will be at dangerous levels.

Sounds good to me, but I don't know silvers (USA, don'tcha know). Mainly, I don't know about temperature stress on silvers. I also did not hear if you are feeding or not and would think no food until ammonia drops would be a good idea. I defer to silver experts, however. I would suggest putting the heater on a timer to reduce nighttime temperature drops, trying to keep temps in low end of the healthy range for silvers. The goldfish will be fine with no food and low temps.

I am not sure if land plants suck up ammonium ions as many water plants do, but perhaps there is something that would help, like a pot of mint (don't let it loose in the growbeds!). Something that is already fairly large and will grow fast in your climate at this time of year. Hmmm....or maybe wheat or radishes from seed? (Note: this is even more speculative than my normal ideas).

More obviously, have you seeded your system with some bacterial muck from an existing cycled system? This is by far the fastest way to get your ammonia and nitrites down permanently. It is also a great way to spread disease, so get the bacteria from someone you trust! 100ml of slime from an aquarium sponge filter or 40kg of gravel from a growbed will do wonders, even a handful of the muckiest gravel from a cycled system will help a lot (will make it cycle in a week or two).

Good luck!