Keep in mind that eels are amazing escape artists! You will need a covered tank as well as your overflow.

I guess that's a good point. This tank is running on a canister filter, no sump. I have an in tank skimmer and I've looked at covering the tank in the past but with the equip coming out, made it a bit challenging to keep it clean looking. Will see how this progresses.

I made a maze of 1/2" pipe that was placed under the sand the eel very rarely left this except to eat and peek out lol

That's a great idea. I'm still working on my 180 and finally found some brutes for water. Hopefully get that rigged up this weekend as all the water I make on the weekends is topping that tank up and I can't keep up. Ive just got snails, crabs and a couple of softies in the 55 ATM, so as soon as we get better set up, will start looking at what it will take to get these cool fish! Hope you won't mind offering advice!

Anytime.

Well the first trick to these tank mates is adding seahorse first, then a fully trained lion after. The horses should be comfortable in the tank without stress and establish a feeding ritual. With a lion in place already it may be more territorial, then add a stressed seahorse and a ton of food in attempts of establishing good eating habits and you're likely to have an issue.

Again my advice is to pick one or the other, lions or seahorses. Once you have experience with both you could consider them as being tank mates.

That's where I will start first and not until I have done some research on them. Funny, this started as lion fish and eels, ended at seahorses. Any good suggestions on good sites or books?