Re: Planning a larger tank
#68
Hello.
You won't need to do a fishless cycle on the new tank. Take your existing medai and squidge it into the new filter when you transfer the fish. Same amount of bacteria, same amount of fish, bigger volume of tank, and you'll be able to add lots more media to the filter for the colony to grow. Rinse and repeat for the 60L. Depending on the filter you could probably just swap them over.
First the bad news, even 450L won't be big enough for a Silver Shark. They get to nearly a foot long, are very active, skittish fish, and need to be in shoals (6+). You'll need something more like 700L and 6'+ for them. I recommend rehoming them ASAP. They don't mix well with plants either.
Corydoras won't like the hard alkaline water that you have I'm afraid, and I can't think of many bottom-dwellers that will, and will also like the tropical conditions that the current stock needs.
Best thing to do with the tetras will be to reduce the pH gradually mixing RO and tapwater over a series of small water changes, or use all RO and remineralising salts to get the desired pH and hardness. Are you using test strips or liquid dropper kits? You'll need the liquid kits as they're much more accurate for measuring your KH and GH (alternatively invest in a TDS meter, which are relatively inexpensive) and you'll need to test every bucket of water you make up.
In terms of water changes you'll need to do 25-30% waterchanges per week on either tank. On my 240L that works out at 5-6 14L buckets, so you're basically going to have to do 10-12 buckets- 150L or so a week. You can either ferry lots of buckets around, or use a bit of kit called a "python".
Loaches, Barbs, Minnows & Shrimp! Oh My!