very good but i never do that before

I log 'big stuff' into my tank thread, that's about as close as I get.
I'm not a big fan of water testing--- I can usually tell when something is looking 'not right' in my tank, I suppose that water tests are a good way to figure out what's wrong, but doing them frequently detracts from my enjoyment of the tank and makes it work instead of a hobby.

I keep a notebook as a "research journal" for my tank and record everything and anything that happens with it.

Big time.

In theory - yes.

In practice - no.

Perhaps a mental log?

I have an Excel spreadsheet that has dates down the side (each row is a new day) and actions in the columns (water change, dose trace, feed corals, etc...). I have an 'X' on the dates and in the column that I need to perform that action for.

So for instance.....I have an "X" every other day to remind me to dose some coral food. I have an X once a week to do the water change. That way I can not only glance at it to see what I am supposed to do that day, but I can also see when I did it last. I change the color of the row so I know I did the action. I have it populated for like 6 months from now. Just cut and paste the regularly occurring things and it is easy.

The only drawback is that I need to look at it once a day to make sure I did the action and logged it. Otherwise I might forget when I did what. But it is easy to remember since I know to update Excel if I ever find myself feeding, dosing, or water changing.

I haven't even considered doing this before... I only have one tank running so keeping a mental log is working fairly well for me, but I may have to start keeping a hard copy one. Although it sounds like something I will be really good about for a few months and then slowly taper off again.

I am about to start keeping a log, more for knowing when I need to change things, like media and lights and stuff since I am going to have a main tank and a frag tank.

I be rollin old school ... clipboard w/ legal pad. Pilot precise V5 extra fine bay bay.

I do take photos often and store them (yes, digitally) according to date taken.

Mentally

I jot things down on the calendar.

I keep mine in a file on my desktop on the cpu. This way , I have a log of levels, and whats in my tank,ect.... Always there if I need to pull it up, and revert back to something. I guess its the OCD thing, lol !

Started keeping a log with my first saltwater tank.

have a little notebook. write down dates of wc, deaths, purchases, test results, and etc.

I just downloaded AquaPlanner Pro from iTunes $2.99. Looks pretty good so far.

I used to write it down, but I don't record water test results anymore. For new stuff, changes, etc. I just look at my thread on here

http://www.aquaticlog.com/