I am sorry but that site is full of misinformation!
Starting with their statement on Tank Volume and Stocking capacity, 10 gallons for 2 to 4 individuals!
This is wrong, Minimum recommended tank size for 2 seahorses is 20g tall or at the least a 15 gallon tall and for 4 it is 29 gallons. So this being said, unless you are going to keep Dwarf sea horses a 7 gallon tank is way to small.
And they also very much need vertical swimming room (18" - 24" + in height).
Then the line about temperature range is also wrong, 68F to 82F Optimum: 75
At anything above 76 degrees too warm even for tropical SH. This is a very important factor, as SH tend to be prone to bacterial infections, especially at warmer temps due to an increase in bacterial count. you may hear "SH are found in 80*F water in the wild", but you must remember that the bacterial concentration in a closed system is infinitely greater than that of the ocean. At this time i am fighting to keep my temperature down below 76, I think I might need to add a couple of fans tomorrow.
As far as using a korilla you might also want to rethink that. Seahorses like to hitch to anything they can wrap that cute little tail around. A korilla is an open pump and their tail can get in and get caught in the prop.
I was going to use one in my tank and before I could plug it in one of my horses wrapped his tail around the front of it and when he let go I was shocked to see how far it stuck into the inside of the pump. You might want to stick with a small maxi jet.
And as far as flow goes, contrary to what allot of people say seahorses love flow. Their are some out there that say you should have very little flow in a seahorse tank but this is not true. in fact sea horses will be more active in a tank with decent flow, they will play in it! You just don't want too much, meaning you don't what it to blow them across the tank while they are struggling to swim against it.
If you want to learn about Seahorses the best resource on the web is
Seahorse.org they have a library of articles that anyone can read, you should read them... They people on that site have tons of experience in keeping seahorses.