Tank Coversion

Question
I already have a 100 gal salt reef tank started about 2 months ago from a store selling complete setups. I decided I would like to change my 55 gal to salt,to support some fish that are not reef compatible, such as lion fish, or similar types. As far as patience it all deals with how much I have available to spend, which is not much.
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-----Question-----
I have a 55 gal fresh water tank I would like to convert to a salt tank. It has a under gravel filter with 2 power heads and a power filter,heater,normal lighting. What else will it need and can I make an aggressive tank at this size?
-----Answer-----
Hi James
Let me start with this; I like you started 12 years ago the same way converting from fresh to salt. Unfortunately I found pretty much no luck with undergravel filters. Answer a few question for me first. Are you looking at fish only? Do you mean aggressive as in species of fish? What type of budget are you on? How much patience do you have? You need a lot of it to get started, can't rush it, or you will have more problems than it is worth. Looking forward to helping you out.

Michael

Answer
Ok, you may not like my answer. I have had both reef and aggressive fish tanks. For my fish I had a 75 gal, with aprox 50 gal sump, 110 pounds live rock, and live sand, protein skimmer, lighting I had 2 x 110 watt vho. This is what I had the best of luck with my FO tank. As a matter of fact it was my first tank. So I didn't start with everything right off. I actually started with the sump sand and a few pieces of rock. then added the protein skimmer about one month later, then gradually over about a years time ended up with all of the live rock. Oh I almost forgot A friend of mine had the vho lighting so that is how I got the light it helped with the coralline algae growth on the rocks. I cycled my tank with a few Damsels for about 2 months. Then added a lion left him alone for about a month, then added a dog face puffer, along with a stingray. then added a trigger last since I found he would be the more aggressive of them all. Everyonce in awhile I would throw a few crabs in to control my algae, although they wouldn't last long due to the puffer. Then the very last thing I added was a Mantis Shrimp to my sump since it was acrylic. They are real cool to watch once they get over their timid stage. It is expensive over a period of time if you do it like that. I would stay away from the under gravel filter, they seem to do more harm over a period of time, but there are still some people out there that would disagree with me. You can use the normal lighting for a while but if you go with the live rock you need to step up to at VHO or Power Compacts for the algae growth. Let me know if I was to long winded and I will try to explain again and condense this down.