I am planning to build a 300 gal. tank and a diy canister filter with no sump. I do not want a syphon tube hanging on the back, I would rather use a bulkhead. Are there any problems with this type of setup?
The first thing that comes to my mind is always keeping the water level above the bulkhead so as to not suck air into the filter. Is there a specific reason you don't want to build a DIY sump instead of a DIY canister filter?
This tank is going to be a freshwater planted tank. I can build a canister for less than a a trickle filter with equal filtration. A sump would just be another piece of equipment to build. I would place the bulkhead low enough, that with the proper plumbing I could also use it for water changes, and would not have to worry about losing a syphon.
I would advise careful thought before doing the DIY canister if not already done one. I see very few (none?) that come out with something I would want to deal with over the long haul. I often get the response that it is done on U-tube, etc. but then I also have to point out that there are tons of bad ideas on the internet!
I tried the DIY canister filter years ago and it was nothing but a headache! So I spent the money on one of the larger Eheim canisters... SO MUCH EASIER IN EVERY WAY. Then I bought an used tank that came with a trickle (wet / dry) sump and I will never go back to a canister filter. The expensive Eheim sits on the shelf.
Trickle sumps are a hundred times easier to maintain. I don't have to pull the whole filter out from under the tank to clean it. I just pull the pad and sponge out of the sump, rinse them off then put them back in. I don't even have to cut the water flow (pump) to clean it.
I paid about $120 for the 5 gal wet dry that sits under dirt bottom planted my 35g hex tank. Worth every penny! You will probably have close to that in plumbing fittings once you get you DIY canister working how you want... been there! My filter needed a lot of cleaning initially due to the dirt substrate, I am glad cleaning was so easy.
May I inquire about what you are going to use for a canister for your DIY canister?