Quote from: floridaman86 on Today at 11:33:31 AM

I have a futurebit Apollo miner. Mines at about 3TH.

I bought it about a year and a half ago. Initially it mines about 1,000 sats a day. However, over time it kept going down. As of now it's averaging about 600 sats a day.

Why is it mining less? The halving hasn't happened yet

Also, I have been mining with Braiins pool the entire time, if that makes any difference

Your question = what is mining difficulty ?
You should read this:
https://www.bitcoinmining.com/what-is-bitcoin-mining-difficulty/

https://en.bitcoin.it/wiki/Difficulty

Quote

What is "difficulty"?

Difficulty is a measure of how difficult it is to find a hash below a given target.

The Bitcoin network has a global block difficulty. Valid blocks must have a hash below this target. Mining pools also have a pool-specific share difficulty setting a lower limit for shares.

Difficulty is increasing as much as people are adding hashpower to the total network hashrate.
Difficulty can decrease too, if the total hashrate is decreasing.

You can look at the total hashrate for the last 3 years:

As you know, more hashrate = higher difficulty in order to keep a 10 minutes block interval.

So, for the same given hashrate, higher difficulty = your part of block rewards drops