The waste ink error is based upon time instead of actual volume in the tank. You can reset the counter by the instructions below.

Waste Ink Counter Reset.
(1) Turn off the printer.
(2) Press and hold the STOP/RESET button, then press and hold the POWER button.
(3) Release the STOP/RESET button, Next press and release the STOP/RESET button two(2) more times in
succession. Note: you are still holding the POWER button). The printer's carriage will "reset"
or move momentarily. If the above was properly performed the printer will enter the
"Service Mode".
(4) Press the STOP/RESET button 4 times, this will select the clear waste ink counter function. The lamp
will alternate (change) color with each key press.
1. Service/Factory test printout, including ink sensor check.
2. EEPROM - Info printout.
3. EEPROM - Initialization.
4. Reset the Waste ink counter.
5. Printer model setting. (More selections beyond this point - However it is best leave them unaltered - You have been warned!)
After selecting the desired mode (eg 4), press the POWER button to "set" the change, and return to the top of the function selection menu. Press the POWER button again to restart the printer.

Tap the power button again and see what it says when it comes back on.

Doing some more looking, is it possible it might be a error 5B00 instead of 5800?

That is a different error. I found that one on Canon's website. Below is exactly what canon says.

Issue: ERROR LCD: Error Code 5B00

Solution: The MX310 may require repair

Unfortunately, the issue you describe seems to indicate that your product requires repair service. Canon has excellent service options and we are eager to provide any assistance you may need. Click the link below to locate an authorized service facility and obtain further instructions.

Find a Service Location

If you still have questions about the issue you are experiencing, a Technical Support Representative will be happy to answer any question you may have. You can contact us through the email link or phone numbers listed below.

• Obtain Support by Email
  
  
• For toll-free technical support*, please call 1-800-OK-CANON (1-800-652-2666) during regular business hours (currently Monday-Friday 10:00 a.m. - 10:00 p.m. Eastern Time, excluding holidays).
  
  * There will be a pay for support charge if your product is out of warranty (see next section, below).
  
  
• Toll-free TDD Support Line for the Hearing Impaired is available Monday - Friday (excluding holidays) at 1-866-251-3752
  
  
• Technical Support is available for Customers in Canada at 1-800-OK-CANON
  

If your printer is no longer under warranty :

• For toll-free technical support*, please call 1-800-OK-CANON (1-800-652-2666) during regular business hours (currently Monday-Friday 10:00 a.m. - 10:00 p.m. Eastern Time, excluding holidays).
  
  *Pay for support is required on all units outside their original warranty, unless covered by a Canon Extended Service Plan. If it is determined that there is a hardware failure, you have the option to purchase a new or refurbished product from our current product line, which includes units with Canon?s new ChromaLife inks, PIXMA Technology, a limited manufacturer?s warranty, free next business day shipping and discounted pricing. If you elect to take this option, the pay for support charge will be canceled.
  

So we may better assist you, please make sure that you can access your Canon product and have the following information available when you call:

• Product model name and serial number.
  
• Computer's operating system; for example Windows XP.
  
• Message displayed when the problem occurred.
  
• Steps you've already done to try to solve the problem.

We look forward to helping you rectify the issue you are experiencing and are always available to provide any assistance you may need.