Best time (of day) to fertilize? (and another question) - Tropical Fish Keeping - Aquarium fish care and resources
LinkBack Thread Tools
post #1 of 3 Old 07-15-2010, 10:00 PM Thread Starter
Austin's Avatar
Best time (of day) to fertilize? (and another question)

Hey guys I was wondering when I should be trying to fertilize.

Might be a dumb question, but I often change my fish tank water in the evening, and the light goes off almost right after. Since I use aquasafe I don't want it to affect my fertilizer, so I usually wait a day to add the fertilizer. Lately I've figured through logic that it might be better to fertilizer 12 hours later in the morning right after the lights come on - so the plants can not go an entire day (until evening) without nutrients, so the algae doesn't get the upper hand for a day. But, I'm wondering if this makes any difference or not?

Another question is, in my 10g aquarium I have fry and I like to change the water more than weekly. If I was to change the water every other day, how would I fertilize?

Another example was that I wanted to give my 44g a bit of fertilize since it probably needed some. But I was thinking of changing the aquarium today. Is it ok to give it 1ml of flourish (recommended for 12g), or do I need to dose the whole thing since I'm going to change the water today? Thanks! :)

"He situates himself in relation to time. He takes his place in it. He admits that he stands at a certain point on a curve that he acknowledges having to travel to its end. He belongs to time, and by the horror that seizes him, he recognizes his worst enemy. Tomorrow, he was longing for tomorrow, whereas everything in him ought to reject it."
Austin is offline  
Sponsored Links
post #2 of 3 Old 07-15-2010, 11:06 PM
Byron's Avatar
I think the solution to the first question lies in altering when you do the partial water change, and I suggest this because I think it would be better for the fish. Any sort of work in the tank is going to "bother" the fish to some degree, and within an hour before the lights go out is getting them hyped up at a time of day when they are settling down; I expect this must be stressful. I have always carried out tank maintenance in the morning, about an hour after lights on (or later). I use the same strategy with feeding; many writes will tell you not to feed fish just after the lights come on or just before they go out. Much the same thinking. Even people are told not to eat heavy before retiring.

Fish expect day and night about equally; if you have the light on a timer and it is consistent from day to day, the fish will become accustomed to the time. Shortly before lights go out, they begin to calm down, some more than others; I can always sense the last hour or so because certain fish species behave certain ways at that time, almost like getting ready for bed. To suddenly throw them into disarray does not seem prudent.

They sense routines too. I always feed them somewhere around 30 to 90 minutes after the light comes on in the morning. They know; when I enter the fish room in the morning, they come to the front expecting a feeding. When I go in at other times of the day, they do not, ever. On the days they have a treat in the evening (frozen bloodworms 2-3 times a week) it is around 5-6 pm. I have three spotted woodcats in my 115g; they are nocturnal, spending the daylight in tunnels in the wood (hence their common name), only coming out well after total darkness. But they love bloodworms and quickly learned when these are more likely to appear. If I go in to the fish room around 5 or 6, there they will be, at the entrance to their respective tunnel, peering out. They wait. If I slide open the glass top, they are out racing around the wood in anticipation. They never come out at any other time during daylight, only in the evening.

To the fertilizer, I agree with you that adding it in the morning makes more sense, and I do that; plants photosynthesize during the daylight and those nutrients are essential.


Byron Hosking, BMus, MA
Vancouver, BC, Canada

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian. [unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]
Byron is offline  
The Following User Says Thank You to Byron For This Useful Post:
Kro (07-15-2010)
post #3 of 3 Old 07-15-2010, 11:13 PM
Gold Member
aunt kymmie's Avatar
Great info, Byron. Switching my ferts to the am now. Thanks!

If you don't stand up for something you'll fall for anything...
aunt kymmie is offline  
The Following User Says Thank You to aunt kymmie For This Useful Post:
Kro (07-15-2010)

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Forum Replies Last Post
Feeding time question Nople Cyprinids and Atherinids 1 03-23-2008 10:10 PM
Long time fish lover first time forum poster Dk Introduce Yourself 7 02-13-2007 07:04 PM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome