Note 3 - Inventories (Details Textual) - USD ($)	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Inventory Abnormal Production Costs	$ 112,000	$ 206,000
Non Inventoriable Fixed Costs	90,000	467,000
Spirulina Products [Member]
Inventory Write-down	$ 22,000	$ 256,000

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 330
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483080/330-10-50-2

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration