I have a pair of young Oranda goldfish who I'm very fond of and I'd appreciate some experienced people's advice on a few things. I would also very much appreciate it if you didn't point out how much of an idiot I am, thank you.
If you like you can just skip to the bottom where the questions are and avoid the essay.
Some tank history;
Note- I still don't have a water test kit, so please don't ask about water parameters. It's on my to-buy list for next payday.
Between July and October last year I was keeping 3 goldfish in a hexagonal 60L filtered tank, and they were doing well and growing. And I thought what the heck lets get a couple more. Dumb, I know.
I bought the two Orandas in October, when they were 6 months old and about 5cm long (including tail). When I got them they had some barely noticable head growth.
They were homed in the 60L tank with the 3 other goldfish. While I had no serious health issues with them, I was having to do 30% water changes every two days to keep them happy. Obviously there were faaar too many fish in that tank.
In January I was gifted another 60L tank and a small filter. I set this new tank up using tank water from the other tank and left it to cycle for a few weeks, then transferred the Oranda's into their new home.
Since then, I've been doing 15-20% water changes twice weekly and vaccing the gravel, and I've had no problems with either tank. ((The only issue I had was when one of the Orandas got himself impossibly stuck inside an ornament I'd bought off TM. We got him out and though he was missing half his tail and a lot of scales, he's recovered very well and is totally fine now.))
The two Orandas have grown a bit - they're now more like 7cm, but neither of them have any head growth anymore, which is quite depressing and brings me to the reason for posting this.
I really really want to do the best I can for these fish, but I'm a student and on a very limited budget.
But I intend to spend some money and buy another tank, a bigger one. Currently I have my eyes on a 125L tank, as well as a Eheim 2010 filter.
Now for some questions;
1- Is a 125L tank, in your honest opinion, big enough for two Orandas when they're full grown? If it's not, I might as well save my money a bit longer and get something bigger still.
2- Aside from increasing the tank size and better water quality, what other factors influence wen growth?
3- I read that high-protein foods help. Currently I'm feeding my fish nutrafin flakes, frozen/freezedried bloodworms, peas and gel food. And I have some Hikari Oranda gold on the way. Which foods have people found to be best?
On a slightly different note, my tank decorations are all artificial, plants included. While I do love the idea of a natural tank and would love to try it, I have a few worries about it. The Oranda's tank is in my room, which is in shadow all day everyday and the only house plants I've ever had any luck at growing in here are ferns. I do have a light for the tank, but the fish refuse to come out into the open if I turn it on.
Would plants manage alright without light?
Does having live plants make maintence harder?
And do the benefits outweigh the cons?
Thanks muchly. :3