more setup work

on the forty. Although the tank stand seems to distribute and hold weight fine, I noticed it sways side-to-side if nudged. The backing board is very flimsy and not connected to the top shelf of the tank at all, with an open back in the center behind the door (probably designed this way to accomodate a canister filter). It makes me uneasy, I know any kind of stress can cause seals or glass to eventually give way, and it could also cause more vibrations when people walk by, stressing the fish? So bought a sheet of 1/4" plywood cut to fit, fastened with wood screws to all perpendicular panels, top and bottom horizontals. Very sturdy now. I couldn't make it sway when I tried. I'm satisfied peace of mind with that. Had to empty and move the tank to do all this of course, and then level once again. I used wider shims this time and that went better too.

Also bought a second bag of safe-t-sorb. The depth of substrate just didn't look like enough for the size of the tank. It was barely 1.5" and even though the gravel bed in 20 I'm going to bring over is 2-3", it will be a lot shallower spread out in here. As before I sifted the dust and fine particles out of the STS bag, reducing volume by half. The job went a lot easier this time, as I found a plastic sieve (kid's beach toy) with holes just the right size to sort to the particles size I want. Best done outside on a windy day that carries the dust away from you. Can see the particle difference here.

Soaked the STS in a bucket of water with ferts and baking soda again. I used just 3 gallons of water, and looked at how much baking soda it took last time to get the STS to stop lowering pH. Dissolved in 5TB of baking soda and ferts according to the chart that tells me how much to use for EI dosing in a low-tech 40 gallon. Two doses is 1/8 tsp K2S04, 1/4 tsp KN03 and 1/16tsp KH2P04. I did not soak it nearly as long this time, just 24 hours. For the first half of the day could see bubbles rising, actually hear the substrate shifting around in there as it absorbed water and settled. Like something alive, like watching yeast froth to life in a bowl of water... Next day rinsed the STS (what a pain) and added into the tank before it was filled up once more. Cloudy of course. Wait a day now.

Looking at it again I think  the back-to-front slope is a bit steep, but will adjust that when I add the rest of the plants.