I also use a Shark Steamer and when the grout becomes darker looking I use spray bleach and then steam it. Comes out great.

I have the shark steamer also. I have light almond tile with light almond grout. The steamer doesn't really do anything for the grout. But it's great to get up drips, foot prints and spills. When we first moved into our house, I had DH convinced that the grout was dark brown. Till he noticed the color next to the baseboards. I recommend having them cleaned and sealed by a professional. Then it will be done once and for all. Oh, if you do get a steamer, get the extra box of replacement pads at the same time. It seems like they change the head shape every few years. Mine is no longer available in that size, but thankfully, I have 4 pads that are reusable after a wash in the washing machine.

I understand your problem because I have light grout also. What I ended up doing was mopping the floor with bleach in the water. It really helped to make the grout look better. You might give that a try.

Tried a Shark twice at more than $100 each. Each one could only be used on the floor and each one died after a year. Seemed to know exactly when the warranty ran out. Now we have a VaporClean steamer. It is a canister with a hose and different nozzles. My husband loves it. So far he has used it to clean floors, the stove, the microwave, outsides of cabinets, countertops, bathroom tile, spots on the carpet, and even to get bugs off the car. We live in Florida and it's lovebug season right now! This is an expensive tool. I think he paid $500 for his, although they are on sale right now, but he believes it has been worth it.

I buy any one on sale or the cheapest and use it until it dies, usually about 2 years then buy another one. I have ceramic and laminate floors and can't tell any difference using the high end steamer from the cheap one. Steam is steam.

The last two I bought was at Black Friday sales two years ago for $25 each. I think they are Bissells. One is still going strong and one is a spare still new in box. I have a hand held steamer and it works great for non floor cleaning.

I have a Dyson animal and I love it. It is the best vacuum I have ever had and I love it. I would highly recommend it. As for a steam cleaner I do not recommend the Shark. I had one that I loved. It lasted about 1 1/2 years and broke. My sister borrowed mine to try it out and loved it. Her daughter also bought one. All three were broken after 1 1/2 years or so. My sister and niece are clean freaks so they probably used theirs a lot. Me I don't clean like they do and mine didn't last that long. I have been told that the Reliable brand one is good but have not tried it yet.

I have an Oreck...what I like about this one is that you can control how much steam is released..more for tile with grout, less for hard wood...I had a shark before that and like it a lot, too, but now that I have the Oreck, I like it best! Had zero luck finding parts from Shark when mine broke...that's why I switched brands..I HATE these disposable appliances we are forced to buy now where you can't get a 2 dollar part for it..they want you to buy the new item...haven't had to find an Oreck part yet, but hoping they are better!

I have a Bissell steam mop. It does a good job on the ceramic tile but forget about the grout. It doesn't clean the grout at all. I don't think there is anything out there that cleans grout besides getting on your knees and scrubbing with an old toothbrush.

There is a grout cleaner, not sure what it is called and gave up with the dogs. But it works well.

the red shark professional lift away is AWESOME. I love it. I also have the Eureka Enviro steamer. I did alot of research before buying a floor steamer and I got this because it put out more steam and has a longer cord. I tried the shark steamer and I just wasn't happy with it