If your going to use a 20 or 30 gallon I would go new. You can get them cheap enough. Only reason I say new over used is if its your first time building a sump- silicone needs a pretty much perfectly clean and dry surface to adhere correctly. You should make your first one as easy on you as you can, youll see when you are siliconing between the bubble trap baffles that are only and inch and a half apart.:spin: For a few bucks more you can save yourself alot of cleaning.
i completely agree.
do it yourself! so simple. i have build about 15 sumps and around 7 or 8 external refugiums for myself and friends. i have made them for tanks starting at a 29 up to my buddies 150. its cheap, simple, and effective. sumps/wet drys are expencive. IMO (if you feel i say something wrong then sorry but i have done it multible times and always turned out amazing) all you need
is a tank (NEW)
measure out your plexi (remember its inside measurments, usually its 1/4 less. for instance if the width is 12 inches, get 11 3/4. it all depends on how thick of glass it is)
All Glass Aquarium sells silicone, if you cant find it a local hardware store sells one that says aquarium safe and has a fish picture drawn on it. if you cant find that then order it online, dont just assume if it says its waterproof or something its ok, its not.
next is just to build it. first section a peice of plexi 3/4 way up and around 5-6 inches wide, this is where your water flows into, then if you want a fuge make room for your fuge. that i dont want to say on size because its your choice, if you dont have a big enough tank that you cant fit it then make room and put your skimmer and some rock there. then a bubble catcher where is really 3 peices of plexi. a peice of plexi going up like the first one i said but a TINY bit shorter, then another that is lifted off the bottom, not touching the bottom of the tank around an inch or 2 up yet taller then the first peice so its forced to go strait down, then another peice like the first but again a bit smaller. then your pump and your good to go. if you want to make a row for sponge or whatever do it right after the bubble catcher or right after the first plexi in the begining of the tank. bam, your done. here is a few pics of the last one i made. its old and bag angled pics but hopefully it may help.
ALSO!!!!! DRAW IT ALL OUT FIRST!!! you may laugh but this is what i do before i build my set ups. this pic i drew up when i was bored and its really gay but its the though that counts!!! hahaha this is for my friends tank im doing next week, its a 65g with a 20 or 30g sump.
