Can I Contest/Stop a Wage Garnishment That Has Been Ordered

My question involves collection proceedings in the State of: OH. After being found in default of my student loans, I began paying the loan back. After about a year, they (DOJ)switched to e-pay. I lost track of the site to make payments, and stopped paying. I never received a notice to make a payment after that. I sent several emails to DOJ to try to find out where to send payments to, with no response. After receiving notice that they were going to garnish my wages, I contacted the DOJ in Columbus. I was told my options were to do nothing, and they would take 25% of my salary. The other option was to fill out a financial statement, and that we could try to work out an agreeable amount to be garnished.
Two questions for you. Is there any way to stop the garnishment from beginning, and just continue to make payments? Also, in the financial statement, it asks for our gross earnings, but that doesn't account for insurance, Aflac, union dues, retirement, or anything else that is coming out of our checks. Which means our take home is way less than what we gross. Is that right/fair (not that the government cares about fair).
I saw a term in another thread. What is a slow pay motion, and is it an option in this case?
Ultimately, I'm trying to keep from having a garnishment on my credit history. I do not have an attorney, nor have I consulted with one. Do I need to? What options do I have, other than letting them garnish my wages?

Can I Contest/Stop a Wage Garnishment That Has Been Ordered