Plywood Tank Build

Hi All,
I have decided to start a new tank build and its one I haven't done before so I'm looking for a bit of advice. My own tank is getting old and scratched and has started a tiny leak so rather than try repair, Ice decided to build a new one. The space I'm putting it into is a bit of an odd shape so a full glass tank is not really an option. As a result I've to decided to completely utilize the space and use the plywood method. I've seen a few threads already around the plywood method but as we all know, each build is different and there is never any harm in getting advice from people that have been there before. I've sourced the plywood and all the wood I could need for he stand but the first hurdle I've come to is the sealant. The tank will be around 1000lt when its completed so I had set my mind on the method which is hugely popular in the states. I was going to waterproof the whole thing using liquid rubber sealant but I see on here a few of you have used epoxy. the 2 main reasons I decided on rubber initially is the fact I've a newborn baby and the liquid rubber is practically odorless as opposed to the epoxy. its also (from my initial price sourcing mission) cheaper to buy when constructing a big tank.

So now I'm coming to you guys, has anyone here used liquid rubber and which would you advise ?

Oh 3 sides of the tank will be fixed directly onto walls so the support that the epoxy gives is not so vital.

Nice to see another thread. Liquid rubber isn't fail safe and more to the point has failed more times than I try to remember so epoxy would be my choice for its reliability. You could use g4 (I think) pond sealer if ye like but I would always recommend epoxy.... if you have till later I'll pm ye a link to where I got it or I have some there at a good price
As for aquarium silicone, theres a grp supplier on ebay in ireland that sells a large number of tubes for about 60e... I got my acetone off him and would recommend him
Whats the tank dimensions?

Dimensions are 1741 x 465 x 1220 (L x W x H and in mm. Approx as the location i'm building it inst completely squared)

The rubber i was looking t is on the following link. Its a little over 70 for a 5 L drum of it.
rubberizeit.com/

Definitely Davey, pm me the link and I'll check it out. or let me know your good price. for a tank of that size how much epoxy would you think would be needed ?

Let me know the eBay sellers name too. I don't use eBay (bad experience with them before) so I use amazon but I will find someone with an account to get me some.

i think the rubber route will be best for u as its going to be far cheaper than epoxy, if u need any clear silicone for ur build try wurth in ballymount ul get a great price for quality product

I have 10kg of epoxy for 100e if thats tempting. Thats more than enough for your tank and its the stuff pictured in my build thread below.
That height is gonna crucify you tbh, 1stly you will need to build a stud into the front to take the pressure so it'll be double the plywood too along with a fortune on glass...
I'll get links for ye as soon as I'm home

I'm using 18 mil thick plywood. The bottom will be a double layer, the back and 2 sides will be securely mounted directly onto walls so I'm happy they will be safe. For the front I'm going with 18mil glass, the top of the box will be cut to have 2 central struts and then 2 additional wooden braces will be added to add extra strength. These will be secured directly into the wall and then attached to the front panel. This adds extra strength and gives me a mounting point for my lighting.

I understand the part where the sides and back will be fixed to the walls but the front will need a better fixing than just into the edge of the 2 side panels. Without a frame you'd be surprised how much movement will be in the front with it only being 18mm plywood you will seriously run the risk of a leak due to weakness. Obviously your using the full width of a sheet of ply as your height but thats alot of pressure (I'd be interested if someone could do the maths on that )
My tank was only 33inches high and I'd have to use 22mm ply along with corner fillets and fully fibreglassing it with resin and matt to take the pressure... yours is 48inches high with 18mm ply and maybe sealed with epoxy, the front will be a weak point imo pal
Have you looked at www.monsterfishkeepers.com for ideas?

I'm putting a sheet on the top too, this will be screwed into the sides, back and front (with 3 holes for access.) I'm also adding 2 lengths of 4 by 2 which will be fixed to the front panel and then mounted across the tank and directly into the wall. Similar to the pic below. After this though. I think I'll add the third row in.

After daveys advice. I've sourced a large amount of Fiberglas so I'll coat it's full interior with 2 layers (4 in the corners and edges). Then on top of that I'm going with 5 layers of epoxy resin. So that has giving me some ease around the strength issue.

Curious though, epoxy or polyester resin?

Ive no advise to offer just a request for a pictorial account of the tank build. Its my ambition to build my own very large tank

think Davey has u going in the right direction,multible layers glass matting or sheet,with epoxy or polyester.i made ply think 250 gallon epoxy glass with a potable epoxy sealer,worked great.built a 180 ply with polyester gass sealing worked grand,faster method but smellier.my main tank is a concrete build with 3 windows,2200 gallon including filter,its plastered and skinned with glass andpolyester resin.it has 3 foot deep windows19mm,any deeper think u may have to go at least 25mm.with ply,a triangular section timber in right angle joints adds a lot of strenght and wakes glassing alot easier as glass fiber doesnt like bending at right angles.flic.kr/p/eaW9Dx this is a 8x3 foot x 18" i built shows the triangle fillets.
flic.kr/p/brVaJKthis is the 2200 gallon.
flic.kr/p/bBguJ6 3 foot deep windows,tank is 4 foot deep