I’m building a sump out of a 20 gal long tank, and I’d appreciate any feedback. The dimensions are 30” x 12” x 12”. Baffles are labeled with roman numerals and will be made of either opaque 1/8“ or ¼“ acrylic. If I run out, I might use 1/8 polycarbonate. There are three chambers, and water will flow from left to right. To start, the center of two 1” bulkheads located at the same height will be 5”. There will not be socks.
Chamber 1 will be 16” horizontally, and will contain a protein skimmer. At the far end, baffle II rises 8” from the bottom. There will be a chaeto lamp above chamber 2. I’m thinking of blocking some of the light from the lamp by placing a baffle above baffle II. There will be a gap of 1” between baffle I and II through which water may flow. Baffle I will extend to the top of the tank.
Chamber 2 will be 8” horizontally, and will contain chaeto. At the far end, baffle III rises a total of 7.5”. There will be a 1” weir cut in to the top. Baffles II, IV, and V will form a bubble trap. Baffle IV will extend from the top, until 2” from the bottom. Baffle V will rise from the bottom to a height of 6.5”. The gaps between baffles III and IV, as well as IV and V will be ¾”.
Chamber 3 will be 4” horizontally, and will contain heaters, a place for additions of various things, and sensors. An exit bulkhead will be mounted with its center 2” from the bottom.
I have a few issues that I’m trying to work out. First, I want to enclose at least part of the sump so as to limit salt spray. From a practical purpose, the entire thing will probably be enclosed with three acrylic panels, one over each chamber.
For chamber 1, I can’t have a flat lid sealed against the skimmer body. If I were to do this, a skimmer overflow would flow onto the top of the lid. So, I need a flat lid with a hole cut in it. Resting on top of this hole will be a tower that will enclose the entire skimmer. I don’t know if this is possible. I have roughly 24” of vertical space under my tank, and the skimmer is roughly 22” in height. One possibility, which I’d rather not do, is to have the sump outside of the cabinet. Another is to have this part of the lid in pieces. I can put the bottom of the skimmer in the tank, but the flat lid on, put the top part of the skimmer on, and then sandwich the skimmer in from the sides with the tower. The tower would be composed of two parts: the first part would be three walls and a top. The second part would be a fourth wall that would bolt or tie onto the assembly of three walls and a lid. This would potentially make emptying the skimmer a slight nuiscance, but maybe it wouldn’t be too bad. The alternative to all this would be to totally enclose the entire sump and skimmer in an acrylic box, which has disadvantages as well. This aspect concerns me the most, and is the most tenuous part of the design.
For chamber 2, ad standard old-school “bell lamp” used for reptiles would provide light for the chaeto. The lid would be clear acrylic, with clear glass on top of this. It would be constructed in this way so that the glass isn’t exposed directly to the sump, so as to avoid leaching of tin. Furthermore, the glass would prevent the lamp from being directly on the acrylic. If this is a bad idea, please let me know.
For chamber 3, an acrylic lid would be held in place by a brick. Mounted in the lid would be addition ports and sensors for ATO, kalkwasser, temperature, etc. There would also be holes for cords supplying the heaters.
As for the baffles, do you think that they are of good heights? I need 8” of water in chamber 1, hence the height of baffle II. As for baffle I blocking the light, is this a good idea at all, or wouldn’t it do much? If this is worth having, is the 1” gap between baffle I and II sufficient?
As for baffle III, of course it needs to be lower than baffle II. At 7.5”, it will be 0.5” lower than baffle II. Is this sufficient? Is the weir of 1” sufficient? Should I have baffle IV to extend all the way to the top (to block light)? I’m temped NOT to have it rise too much higher than baffle III, so as to make cleaning between the baffles far easier. Is the 2” gap below baffle IV sufficient? Is 6.5” a good height for baffle V? This is just arbitrary, really. Is the ¾” gap between these baffles sufficient, or will cleaning be difficult?
I’m planning to use acrylic for the baffles rather than glass for a few reasons: I already have the plastic, I want to avoid introducing tin from glass, and it seems that acrylic works well for most.
So, can anyone offer any suggestions? Thanks.