Live bearers being weird

[Dr.rex]

55gl 4 months old at 80ish, one canister, one hang on the back with aragonite and a mesh filter bag. stocking, duckweed, hornwort, bell pepper and an unknown plant.  pestnails, 12 MTS,  10ish guppies  3 Pilates  4 Molly's and a 7-in pleco, (bad test strip ph7.2) retest 4x ph6.4, gh 300+, kh 120ish. A 0, NI 0, NA 30-40

Does anyone know why my guppies and platys are all hiding up in the corner directly under the outlet of the canister filter, cuz the Molly's and the Pleco are still running around just fine

only changed 5gl 3 days ago and the only thing different is I did not add salt back to the water I changed, and some of them are diving to the bottom and rubbing into the sand like trying to wipe something off of themselves for about a week, hence why I changed water and did not add salt, so I don't know what they're doing, do 1 of y'all of know (edit 3 I think I have bad strips and kits, strip 1 ph 7.2 - 7.6 strips 2,3,4,5, 6.4, 7.6 6.4 6.4, api test kit low ph sold 7.6, high ph 7.8 maybe a 8, so still idk I guess the mystery just gets thicker)

 

 

Edited April 19, 2021 by Dr.rex
Bad test strip, redid 4 times ph 6.4 not 7.2 all other readings the exact same

[Colu]

Ammonia and parasites can cause them to rub on thing in the tank I would add an extra air stone and treat with paracleanse or general cure and check your tap water for ammonia

[Dr.rex]

8 minutes ago, Colu said:

Ammonia and parasites can cause them to rub on thing in the tank I would add an extra air stone and treat with paracleanse or general cure and check your tap water for ammonia

A O, tap A 0, I'll set a cup out and check it in 24 hours but I ran them through the trio 4 months ago and no other new stuff's been added

[quikv6]

That PH of 6.4 seems a tad low for livebearers. Is your PH normally at that level? I have found that a PH change during a waterchange can cause mild flashing behavior.

Although I don't think this is the case, a drastic change in salinity can affect their behavior. Being you only changed 5 gallons without salt, I don't think that would be an issue. You can try adding a small amount of salt back in (to replace the salt that they were use to, and see if there is any change in behavior.

I am assuming you declorinated at the last waterchange. If not, that could cause issues.

Edited April 19, 2021 by quikv6