Ph dropped over 4 days

[Joey Mig]

I have a 38 gal aquarium (actually holds 30 gals after sand and rock) stocked with 1 :4 stripe damsel
1: blue and gold damsel 1: royal gramma 7: hermits. Water tested on 5/14 ph 8 nitrate 10 pm
water tested today ph 7.7 nitrate 0. what would cause this? i have not had to top off tank in between tests and have not added anything between them.

 

[GoVols]

Did you test your ph at the same time of the day, on each test?

How can you go one week without needing to add topoff water?

 

[Joey Mig]

as for the top off i do not know , this is my first tank. the water level hasnt dropped that i can notice . the salinity is staying steady (has not changed at all ) there was maybe a 2 hour difference in the time of day the testing was done.

 

[GoVols]

as for the top off i do not know , this is my first tank. the water level hasnt dropped that i can notice . the salinity is staying steady (has not changed at all ) there was maybe a 2 hour difference in the time of day the testing was done.

does your tank have a closed canopy, or is it open air lighting?

 

[Joey Mig]

closed glass lid only open at back where hob filter is

 

[Joey Mig]

ohh and my lights sucked i have not upgraded them yet , which is why i have no coral yet. the lights are actually under the rim of the tank

 

[GoVols]

closed glass lid only open at back where hob filter is

Co2 might be trapped under the closed glass lid.

Can you crack it open and run a fan across the surface of your water?

 

[Joey Mig]

ok will pick up a fan and try that

 

[Joey Mig]

for now i opened the lid and angled the powerhead on the opposite of the filter up toward the surface to create more ....agitation...waves .....idk what to call it