I just learned something new on another thread - why not to do water changes while the lights are on.
I'm so grateful for this forum, without which I don't think I could ever hope to even dream that I might have tanks that actually work out!
I've been struggling with some tanks of mine that are low tech in theory (except I have been dosing excel recently in low doses to try to turn the decline around.)
I have plants that struggle - very little growth, yellow mottled leaves, diatom algae
etc. I lowered my lighting times, put in a few root tabs, have been adding nutrients weekly and doing the excel in the mornings...
Added hornwort as a floater - within a week it is going yellow too & looks like it's melting...frogbit seems okay.
Also cleaned filters, done lots of siphoning out of organic matter & 10-20% w/c daily, with 50% weekly. I do w/c at night...with the lights on!😱😳
At first things looked like they were turning around quite rapidly - less diatoms etc, but over the past few days the diatoms are back in force and although the plants do look a little better (a little greener & even a new leaf or two) they are far from healthy overall.🙁
Anubias especially suffer - they had a white crusty film on them which I rubbed off...then diatoms, then started looking more perky - and now diatoms again...
So.........could it be the daily lights on w/changes that are untipping the balance in my tanks and making the plants miserable?
Maybe I just do too many water changes - but I read that lot's of small-ish changes are a good thing.😕
How long should I wait after turning off the lights before doing the w/changes?
I'm so grateful for this forum, without which I don't think I could ever hope to even dream that I might have tanks that actually work out!
I've been struggling with some tanks of mine that are low tech in theory (except I have been dosing excel recently in low doses to try to turn the decline around.)
I have plants that struggle - very little growth, yellow mottled leaves, diatom algae

Added hornwort as a floater - within a week it is going yellow too & looks like it's melting...frogbit seems okay.
Also cleaned filters, done lots of siphoning out of organic matter & 10-20% w/c daily, with 50% weekly. I do w/c at night...with the lights on!😱😳
At first things looked like they were turning around quite rapidly - less diatoms etc, but over the past few days the diatoms are back in force and although the plants do look a little better (a little greener & even a new leaf or two) they are far from healthy overall.🙁
Anubias especially suffer - they had a white crusty film on them which I rubbed off...then diatoms, then started looking more perky - and now diatoms again...

So.........could it be the daily lights on w/changes that are untipping the balance in my tanks and making the plants miserable?
Maybe I just do too many water changes - but I read that lot's of small-ish changes are a good thing.😕
How long should I wait after turning off the lights before doing the w/changes?