Hey, I recently picked up a 75 Gallon SeaClear System II from craigslist for cheap, and was wondering a few things about setting up as a planted tank.
1) With the built in wet/dry filter in back, there are a series of passive outflow holes along the bottom of the dividing wall that are only a couple inches off the base of the tank. I wanted to build the substrate layer higher than that and was wondering if there is some way that I can build in front of these holes without compromising the filtration? Maybe with a row of rocks along the bottom that sit in front of the holes or something like a sponge. I could try to layer the substrate above these holes and hope that the flow doesn't disturb it too much, but I'm not sure how this will affect the filtration... and I'm almost positive there would be permanent holes in the substrate from the flow if i didn't break it up somehow.
2) Where is the best place to add pressurized CO2? I read on another post that adding it to the sump would cause an excess amount of loss before it reaches the main tank, but would it really be that severe? I don't have a problem with adding it to the main compartment, one airline hose is not that noticeable, but would the concentration loss still be bad?
3) Is is possible to expand the top cutouts of the tank to make it easier to add the hardscape materials, maybe by an inch or 2? I wanted to use driftwood in this tank but getting it in those 17"x7" holes is going to be a pain in the rear.
Any advice is appreciated! I am going to use this tank no matter what but would ideally like to do what I want with the scape... my biggest concern is the passive outflow holes from the sump to main tank, worried that it will blow the substrate all around that back wall. Here is a link to the tank:
The outlets from the sump pump to the main tank are vertical along the rear right wall panel, and the passive outflow holes run along two thirds the bottom of the tank from the right.
In hindsight I probably should have just purchased a glass tank, but I liked the idea of having the filtration completely hidden and built in... Oh well! Thanks for your help!