I use an app that came with my iPhone. It's call "Notes". Works great!

I'm using an app called AL(aquatic log)to keep track and it's free too.

Ya, I'm the same. As long as my measurement is good that day, I'm happy. If it's not, I take corrective action until it's good again. I track bulbs and RO parts in my head. My head is old, my cartridges might be too :)

Apex Fusion has a note taking system that works. Not as nice as a graphing log or something but I'm sure that's in the works

I made all of my logs in excel and printed sheets out. I keep them in a binder to fill out. Ones that are important to me right now is my vinegar dosing schedule and my carbon/GFO switchouts. But I also have test results, RO/DI filters, maintenance/water change sheets as well. Works good for me!

I Use an app called old fashioned pen and paper record all my water changes my parameters when i notice something weird if i add corals or fish, i have been pretty diligent and i can flip back to say a few months ago and check how many WCs i did or the paramaters

Maybe I'm anal but i kinda like recording it all

I plan on using pen and paper. I am old school like that and it just seems way faster to me.

I actually singed up to make apps but never actually put in the time. I think I may try making my own :)

What are the main things you guy's track?

I mainly keep track of water changes & RODI system throughput. I don't like changing filters on a calendar basis, since that has nothing to do with how clogged they get. It's all about how much water you've sent through it and what the TDS out of the RO membrane is. Also, it's good to know when you're getting close to the 20,000 gallon mark through your carbon filter, if it's rated for that, rather than changing at an arbitrary 6 month interval. I've found the less I mess with the RODI, the better it works. Change the sediment filters regularly, but I'm still on the original 75 gpd membrane and only the second carbon block in over 5 years.

Although my spreadsheet has a page for all the chemical parameters, I don't typically check those very often, unless the tank "doesn't look right". But since I've gone to the trouble of maintaining a spreadsheet, it might as well be able to track that stuff. I don't print any of the info to put in a binder. Don't see the need when I can see it all on the 'puter.

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