This is what I was thinking.
"Up to about 20 grams of fish oil can be well tolerated by most adults. However, such high amounts may not be beneficial and the FDA recommends that consumers not exceed more than a total of 3 grams per day of EPA and DHA omega-3 fatty acids, with no more than 2 grams per day from a dietary supplement. Such high doses may suppress the immune system. Unless medically necessary, such doses should be avoided, particularly by immunocompromised individuals. The potential for immune suppression was highlighted in a review of several studies in animals which found very high amounts of EPA and DHA to dampen immunity, resulting in reduced survival from bacterial, viral and fungal infections (Fenton, Prostag Leukotri EFAs 2013). These adverse effects occurred when EPA & DHA consumption contributed as much as 1% to 10% of an animal's total daily energy intake. In terms of human consumption, this would be about 2,200 mg to 22,000 mg of EPA and DHA daily, which is much higher than provided by most fish oil supplements (typically around 500 mg daily), although the dosage taken to lower triglycerides would fall in the lower end of this range. Commenting on these findings, a researcher noted, "Our main concern here is the hyper-supplemented individual, who may be taking high dose omega-3 supplements and eating four to five omega-3 enriched foods per day." (OSU website, 2013)."
This was from ConsumerLab.com