You're brave enough to invest in such dark times 
I don't know how you guys get free electricity, but if it's free, you'll always be in profit
Soon or later hashrate will reduce if prices don't rise (for ETC, ERGO, RVN, ETHW etc) and you can benefit, but again, with no costs of electricity, you're ahead of 99% of another miners
How much are you earning per day?
[/quote
An investment of $600 is more like a hobby.
NVIDIA GeForce GTX 1660 GPU profit is super when mining ethereum classic 8 cents with free electricity, although there are other coins where the profit is 14 cents.
https://whattomine.com/gpus/53-nvidia-geforce-gtx-1660-super?cost=0.1&cost_currency=USD
I don't know how you guys get free electricity, but if it's free, you'll always be in profit
Soon or later hashrate will reduce if prices don't rise (for ETC, ERGO, RVN, ETHW etc) and you can benefit, but again, with no costs of electricity, you're ahead of 99% of another miners
How much are you earning per day?
[/quote
An investment of $600 is more like a hobby.
NVIDIA GeForce GTX 1660 GPU profit is super when mining ethereum classic 8 cents with free electricity, although there are other coins where the profit is 14 cents.
https://whattomine.com/gpus/53-nvidia-geforce-gtx-1660-super?cost=0.1&cost_currency=USD