Wow. I'm not sure where to begin. Sit down, hang tight, and be prepared for a difficult ride. I have to tell you, of all the posts I've answered in the last 3 or 4 months, your tank may have more potential for disaster than any of them. You have received HORRIBLE advice and very quick corrections are needed.
Lets start with the setup. You say you have a wet dry filter. By definition, this means you have bioballs or other biomedia. These filter medias have not been used in marine aquariums for a long time, due to the fact that they are VERY effective at RAISING Nitrates. This is the exact opposite of what we want in a marine aquarium. A properly set up system will utilize live rock and sand as the only biomedia. Combine this with an effective protein skimmer, which you say you have, and you have a very low maintainance high probabiliy of success setup. Doing frequent water changes to lower NItrates is not a good option, because the large water changes necessary for such results is extremely stressful on the fish and other livestock. You asked for links... so here is a basic article on filtration for marine aquairums:
I would also recommend "The Reef Aquarium" by Jullian Sprung and Charles Delbeck. It is a 3 part series and absolutely an essential read.
Let move on. Your live rock and sand are exactly wrong. If you wanted to do something incorrect and intentionally cause a system to crash, you would be on track. The amount of live rock you have is not even close to sustaining a stable environment. You need to triple this amount of rock. I suggest adding some base rock for starters. Check out marcorocks.com and consider placing a 25 pound order of Fiji dry rock. (be sure to cure it before placing it in your tank). You could then add another 15 to 20 pounds of live rock. I suggest using Craigs List to find some experienced live rock from another marine aquarium, or buying live rock at the LFS that has been there for some period of time. Stores which deal in high volume of marine traffic are NOT good places to buy live rock, because it generally is not cured. You want rock that takes several weeks to months to sell and has no noticable odor.
Next the sand. Your sand depth, again, is exactly incorrect. A marine sytem should have less than 1'' of sand, or MORE than 4'' of sand (max 6''). Anything inbetween causes nutrient buildup without proper denitrification. You currently have a cynobacteria bloom. (the red algae) This is caused by the excess nutrients that are leaching into your aquairum from the sand bed and biofilter, and from the lack of live rock to remove these nutrients efficiently.
Then there is your anemone. You do not have enough experience to care for this animal. They are one of the most difficult of all animals to care for properly and should be left only in the hands of very advanced marine aquarists. They have very special lighting and feeding requirements, and require absolute pristine water quality. You can't provide this. It needs to be returned to the LFS.
Next lets talk fish. Your fish selection is horrible. (Sorry) You have fish which are not capable of living in your aquarium. The mandarin WILL DIE if you leave it in your tank. This is not a maybe, it is a for sure. Mandarine REQUIRE very large populations of copepods and amphipods to live. These populations occure in aquariums with the correct amounts of live rock and sand. Even then, a minimum of a 75 gallon tank is needed to sustain these populations unless you have a refugium, which you don't.
Moving on, the pufferfish need a lot more space to develop a healthy immunity system. These fish are very sturdy and disease resistant, but are VERY prone to sudden behavior issues related to their care. They will stop eating completely, lay on the bottom of the tank, and often just slowly shrink in the stomach area. These are developmental problems caused by the hormones released into the water. This is common for fish kept in smaller aquariums, and these fish are a perfect example. To keep either of these species you need a minimum of 125 gallons, and honestly more like 180 to 400 gallons. You can not overcome this issue. These fish also have to be returned to the LFS.
Oh yes, your Scooter Blennies. This fish is identical in care requirements as the Mandarine Goby. Everything I said about the Mandarine applies, and you have a total of 3 fish with these care requirements. In other words, even in a 180 gallon aquarium, you would probably not sustain these fish for any extended period of time. The fact that they are eating Brine Shrimp is irrelevant. It means nothing. Brine Shrimp do not provide the dietary requirements of these fish. You can feed a child Oreo Cookies, but it won't stay healthy.
On a side note, you have a sponge filter on your power head as a prefilter to the skimmer. This needs to be cleaned several times per week to help reduce phosphate buildup. Normally I would go into detail on this, but you have so many other problems that this is just being picky.
Are you testing calcium and alkalinity and adding buffers and calcium supplement? This is a required part of care for a marine aquarium. For some reason, I doubt Pet Smart explained this.