The price of bitcoin may sink even lower, cryptocurrency trader Ran Neu-Ner says.

"We keep going down, and we're testing new lows," Neu-Ner said Monday of the cryptocurrency market on CNBC's "Fast Money."

"Sixty-two-fifty is the next point," said Neu-Ner, who is host of CNBC Africa's "Crypto Trader." "If it goes under that, we're going to test 5,900."

Neu-Ner said a key level for investors to watch was $5,000.

"That's where the miners look at this and go, 'Is it actually worth keeping the machine on?"' said Neu-Ner, founder of OnChain Capita. "At about $5,000, if we don't get a turn up, then we may see a very different game in mining."

Bitcoin fell below $7,000 on Sunday, plunging to $6,647.33. The 10 percent decline is the lowest the digital coin has been priced in two months. It was at $6,822 on Tuesday morning, according to Coindesk, but still nowhere near its December peak of $19,500, leaving market watchers on edge.

Over the weekend, an exchange in South Korea announced that it had been hacked.

Neu-Ner pointed out that the cryptocurrency market is in its infancy, and these things are expected.

"We're the internet before you had a real browser," he said. "And people are talking about a few exchange hacks. Those are to be expected from an industry that's got a market capitalization of $300 billion; when we expect that one day this thing is going to have $20 trillion [in market cap]."

Rather, what's happening in the crypto space right now is a bear market, Neu-Ner said.

"We can't break out of that downward pattern," he said. "We can't break the 8,000 or 8,500 level with convincing volume."

Regardless, the early investor of bitcoin said now is a good time to buy bitcoin, "If you believe in the long-term of blockchain."

Day traders looking for quick returns might have better luck in other sectors, Neu-Ner said. But investors looking over three to five years should buy, or at least hold, bitcoin, he said.

"It could go to 20, 30, 40, [or] 50,000," he said. "Then no one cares whether you bought it at 5 or 6."