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The pool turned a murky green on Tuesday with Games organisers blaming chemical levels in the water.
Britain's Tom Daley was among the divers questioning why the Maria Lenk Aquatics Centre was closed on Friday as they turned up to practise.
Officials said training was cancelled as "the water must be still for the pool to return to its blue colour".
"Hopefully that means we haven't been diving in anything too bad the last couple of days," tweeted Daley, 22.
The Rio 2016 Olympic Organising Committee added in a statement that athletes could perform dry training at a section of the venue with trampolines, platforms and harnesses.
Venue organisers told BBC Sport the water colour would "take time to fix fully, but conditions are improving".
"The bottom of the tiles became very dirty which we're in the process of cleaning, whilst the water itself is being treated and filtered," officials at Maria Lenk added.
"Again, there's no risk to the athletes and colour-wise it is better than yesterday."
Conditions were fine for Daley's bronze medal-winning performance alongside Dan Goodfellow on Monday, but the water changed colour following the women's competition a day later.
Swimming's world governing body Fina said the water tanks had run out of some of the chemicals used in the water treatment process.
It stressed that there were no health risk to the divers.
The water appeared more blue than green when GB's Rebecca Gallantree and Grace Reid featured in the women's 3m springboard preliminaries on Friday, as Reid progressed to the semi-finals.
Daley is due to compete in the men's 10m platform, which begins next Friday.
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Athletes were stopped from training in Rio's Olympic diving pool as work to turn the water blue again continued.