Phosphate E or GFo should lower the phosphates. The post above is correct. You have imbalance of nutrients. Phosphates bottoms out nitrate.You need to retest your nitrates or do you have a major algae issue? I would start dosing something to remove the phosphates. Start with something with pure pharmaceutical lanthanum chloride to help quickly drop them down. Using a pure lanthanum you wont need much in the way of nitrates to lower the phosphates. But more than likely the reason you have dinos is an imbalance in your nutrients. This happens a lot with people using sulfate reactors or bio pellet reactors. If you want some product recommendations let me know and I can help you out. If you need anymore clarification please let me know!
Couple water changes over the week and dosing to lower phosphate will help