Whitespot can hatch up to a thousand little buggers from out each previous generation Tomont (cyst). So if you only had 10 spots on a fish, they dropped off and went down to the gravel to start the next cycle. So from the 10 little spots, its OK, not too bad, fish will survive, just feed them garlic. Upto 10000 tomites can hatch. In your confined space of 100L, 200L, or 1000L what are the chances for the fish to dodge all those tomites looking for hosts. These Tomites are active 24 hours upto 48 hours. But the longer they take to find a host, the weaker they are to be actually capable to penetrate the host slime layer.
OK I know that is not totally technically correct terms, but in laymans terms, trying to explain it in simple words - they live up to 24 hours to find a host, but they are too exhausted the longer they take to have the power to infect a fish. They are extremely effective within first 4 hours.
In the open ocean, whitespot does not have the same change to find a host. Lots get swept out of the reef by the currents into the open water never to find a hosts. Their effective time period expires and they just become food in the open ocean as all other small particles. The few that can find a host are the only hope of this species to continue.
But these little pests are not that stupid after all. They mostly drop off after sunset. And they hatch about 2 hours before sunrise. So what! What is so important about that? Well, its really simple. They drop off where the fish sleeps. So they can hatch, close by to where they can find possible future hosts sleeping. Wow.... that is clever from a 20 micron creature.
So coming back to the question asked in this thread. Would corals eat them? Even if the corals do. In our closed small little glass boxes, even if the corals do manage to eat up 50% of the buggers, we still have 500 swimming around. Plus they hatched 2 hours before lights on. Most corals are retracted and not actively feeding. Eventually after they opened up, yes, they have a feast. But what happens in the time since they Tomites hatched up to the corals start feeding? In our little boxes? Its hunting time...
All the Tomites blown out of the rockwork into the open water column, will have time to be blown back into the rockwork. Have a second, third and next 2 hours available to find the 10 fishes you got in your tank. What would the infection rate be?
From 10 spots in previous round, to X spots now = tank wipeout.
Whitespot do not kill fish in the open sea. Their infection rate is just too low. They are a "good" parasite. But in our tanks, the chances of finding a hosts of the Tomites are just to good.
