[tunatime]

ok what can make gh keep going down? for the past 2 months or so every time i do my wc i get the water im adding up to about gh6 tds 160 i add it to teh tank and il read about a 2-3 for a day then it will droop back to 1-2 along whit a slight droop in tds. can plants use up a lot of gh? my shrimp tank is starting to get a little over grown whit floaters and moss. the shimp are still breeding and molting and are just as active as when the gh used to stay at 5gh, so i dotn want to do a large wc to try to get it back up and mess whit them so i been doing 10% a week wcs for a good month and its still keep falling to 1-2gh

 

[Bluek24a4]

Whats your substrate?

 

[Simplicity]

1. bad test kit?
2. i believe one user said purigen caused a drop in GH
3. aquasoil is too old?