secchi disk
https://www.youtube.com/watch?v=J2M4McUmU1sis there a specific diameter, or reflective surface that is needed for DIY? spending $40 to $100 bucks seems a bit expensive. for what is a piece of plastic that is painted black/white, and some weight added to it, and a string attached.
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i no longer have a koi/goldfish pond or aquariums. so in that no longer have any test kits. and at moment being a big dumb dumb of what tests i need.
any suggestions for test kits?
any suggestions for water samples that i could take to a lab? as in what specific things to get lake water tested for?
ones that come off top of my head are.
nitrite
nitrate
ammonia
phosphorus
dissolved oxygen
ph