That Tweet is fake news. The Red Tide and the dead fish existed before the spill. Scientists think the algae may be feeding on the nutrients from the spill, but they don't know for sure. If the algae is feeding on it, it won't make it worse, but it could make it last a little longer than otherwise.
Red Tides can't be managed or eliminated. Spanish explorers first recorded Red Tides along with the massive fish kills in the 15th century and then many times in the 16th century. The only way you're going to control the Red Tides in the Gulf of Mexico is to eliminate all of the Karenia brevis, and that's not gonna happen.
Also, no, DeSantis is not focusing on attacking immigrants at the Texas border, legal or otherwise.
Thomas Kennedy, the Tweeter, came to this country as an illegal alien at 10 years old and the only reason he's documented at all now is because he's a DACA "kid."